Always thought they were neat, never handled one, going to buy one in a few months and see if I like it.

Wondering which variant I want? What's out there, ie. available to purchase? What's the difference between them?

Thanks.

I'd look for an A3, not an A3 M1 variant.  The older A3 has a long top rail and it's at a good height for using AR sight and optics.  Most are going to have the standard stock that takes Aug mags, but if you really want to use AR mags you might find one with the Nato stock.  Now that Magpul is making Aug mags, I'd just grab one with a standard stock and get some Magpul mags to use.  I have both stocks for mine and currently use the Nato stock, but that's only because I stupidly sold almost all my Aug mags and haven't bought any Magpuls yet.

ETA:  They don't make the A3 any more as far as I know, so the used market will be your only option most likely.

What's the difference betwen the A3 and A3 M1? What's the A3 CQC?

The A3 is kind of the standard configuration for that generation of the receiver and has a really good rail configuration in my opinion.

The A3 CQC is like the A3 except the top rail is higher, it extends further rearward, and the front end and rail is extended.  It has an 18" barrel I believe due to the front end extension.  It allows for easier mounting of lights, lasers, etc but it adds a bit of weight up front and cost as well.  FWIW I really like the balance of the regular A3 and I've never even held a CQC but I expect I would perceive it as front heavy.

The A3 M1 has an updated receiver to allow for configurations with a "short rail", "high rail", integrated 1.5x scope, or integrated 3x scope.  While the integrated scopes are cool, I prefer the flexibility of a picatinny rail on top.  And both of the rail versions on the M1 are too short in length, again in my opinion.  There may be an aftermarket rail option to make the M1 more like the A3, but I'm not sure where that stands.  Pics and info for the M1 on the Steyr website:  https://steyrarms.com/steyr-aug-a3-m1.html

If I have any of this wrong the Aug experts will be along to correct it, but I think that's the gist of it.  Looking at the options I just think the standard A3 is the best overall configuration, and it's what I own.

CQC is done - unless the AUG A3 ever comes back. I have one and wish I had two. It balances differently than the other AUG's, but recoil and muzzle rise is much different (improved) than other AUG models. It's very fun to shoot, but so is a 16" A1 which balances better than all other AUG's.

The A3 is a great gun, nothing wrong with it if you can find one at a reasonable price used.

The current A3 M1 (or just M1) is also a very good gun and functions IDENTICALLY to all prior AUG generations (depending on the gun's stock). If I were you, I'd pick up an M1 and forego the factory rail (if not interested in the AUG optic options) and get one of the M1 rails about to come out from PJS-steyraug.com.

If I could only have one AUG it'd be a 16" A1. If it couldn't be an A1 it would then be an M1.

+1 for PJS Steyr Aug.

I've bought all my aug stuff from Pete, except my used a3 that everyone gets to shoot.

I will have to look at Pete's new rail but I can't buy another rifle; I have too many commitments already.

Good advice here but it also sounds like the OP is going to have to do some research before he makes a choice.
My advice is that if the OP see's an offer for an MSAR (AUG clone) - AVOID it entirely.

I prefer an AUG that takes AUG mags...and with Magpuls new Steyr type mag - nothing but WIN!!
AUG mags are pricey but not too bad. I usually stock up on sales when I find them.
Nothing against AR style mags, since I also run a Tavor BUT the Steyr stock that use's AR mags deletes a couple
of good features such as the BHO and the ability to change to left hand ejection.

I also prefer the AUGA3 long rail over the AUGA3M1 short rail. I was not impressed with what the factory optics offered.

1st off you need to decide what stock you want - Standard AUG magazine stock or NATO version that uses AR15 mags.

Here are the recent versions available:

Steyr AUG A3

You would have to find old stock or buy used.  Some of the top rails were slightly longer.   Extended to half way of the barrel.

Steyr AUG A3 CQC

This was a Pete Athens/ PJA Investments PJS SteyrAUG Website  exclusive.  Not many made & would have to find used.  Extended top rail with extended forward quad rail.

Steyr AUG A3M1

The current release with 3 top rail options - Scope (1.5x or 3x options), long rail & short rail.

Steyr AUG A3M1 with Pete's new longer rail

Thread found here
Pete/PJS just announced/leaked a new longer rail.

2nd you would have to decide what barrel length you would like.  Pretty much every option shown above came with a 16" sometimes you could find a 18" or 20" but pretty much most of the recent AUGs on market come with a 16."
I have read that you could call Pete/PJ and order whatever rail/barrel combo you would like.

Apologies to an anyone I pulled pictures from.

I would say call Pete to see if still doing the conversion from A3 to CQC. If you still want the CQC conversion.

CQC is front heavy a bit to me. But it is worth  having the extra rail space in a small NonNFA package.

Once again you are giving incorrect advice on the Nato stocked AUG. I broke it down for you a few months ago in another thread, and you are still spreading misinformation.

Op, I have no clue if you are considering the Nato stock, but it DOES have a BHO. As in you fire the last round of the mag and the bolt locks back. It does not have a bolt release, you have to run the charging handle to drop the bolt.

I guess I got my vernacular incorrect.

Yes, any AUG will lock the bolt back on the last round fired.
The NATO stocked AUG does not have an actual dedicated "bolt release", the shooter must use the charging handle to drop
the bolt on a fresh mag

The regular Steyr AUGA3 stock has a dedicated bolt release where the shooter can just push a lever on the left side
of the stock and drop the bolt on a fresh mag, without using the charging handle.

Aside from just dropping the bolt on the A3 - the bolt release can also be used to assist in locking the bolt back (open), when there is no mag in the stock. (It's a nice feature to have)
My mistake...

I ended up going with a A3 in NATO stock.  Wanted the longer rail for whatever optic choice.  Also wanted the ability to use AR mags.

At the time I was not too fond of the two new top rail choices.  Too short, both of them, & reminded me too much of the MSAR rail.
Today I would try to find a A3 model or buy a A3M1 from Pete with that new longer A3ish that he just made.

The bolt release is a non issue.  The firearm is so short that its just as easy to quick pull the handle or flick it off its ledge at the back (like a HK) as it is to reach back by the mag & hit the button.

I previously had a MSAR that used the AUG styled mags & had a bolt release button.  Do not miss the button at all & do not miss having to pack, carry & organize for different mags.
If the AUG will be your only rifle then sure buy the normal stock - the mags are great (except when you try to use them in pouches - in that area they snag) but a little pricey now by comparison.  If your just adding to the stable figure in at least another $100 on top of the price for 5 mags.

I'm going to look for a white Aug A3 M1 and install the new aftermarket rail.

Call PJ first and see what kinda deal he can offer..
He is very well respected here.

I disagree with this statement. I find the A3 release to be noticeably quicker. One's hand is already near it after inserting the mag.

After shooting an A1 for years, the bolt release on the A3 stock was beautiful for reloads.

(Friend came over from Ireland (former Army) and was very jealous of the release...)

I got mine with the 20 inch barrel, and never looked back, Absolutely my favorite gun.

The new A3 M1 with the long high rail is great. With the 20" barrel I'm using a fixed 3x optic similar to an ACOG and it's awesome. With a shorter 16" barrel I'd use an aimpoint and call it good.

A couple reasons to have the long rail on the previous A3, if you are running NV in front of your optic, or something like a ATPIAL, or if you think BUIS are a must.

A3M1 with a 20 and I like it so much I have decided to skip the Aimpoint I WAS gonna put on it and I am going to go with 1/4 or 1/6 variable, illuminated optic.

I am stunned at some of the shots I have made with this gun so far!!!!

I have an A3, an M1 with the 1.5, and a M1 with the short rail. Haven't shot the last one yet. The A3 I've had longest and it's suppressed so I shoot it most often, but I love the 1.5x.

I've always preferred the 20 inchers if I could get them. My A3 has the 16 inch barrel. Love that gun. But my A1 has the 20 inch. And my HD A3 M1 has a 20 inch with an optional 16 inch if I want. I run the 3X fixed optic on my M1. But also have an Aimpoint micro, T-2 on top of the 3x for CQB/in the house/whatever. The M1 will wear a suppressor when it gets out of jail. Even with a 20 inch barrel, the M1 is still 2 inches shorter than you average 16 inch AR (with wear I run a collapsable stock).

That "shortness" even with a 20 inch barrel is what is so darn attractive.  Too, I don't have a collapsible stock plucking my beard out, either.  The advantage of the AUG really balance with the "disadvantages" of a bullpup to the extent that I am already nearly as comfortable running with an AUG as I am one of my Colt ARs.

The practical accuracy mine is exhibiting with both 55 and 62 grain Federal ball rounds has also really sold me.

I have a Steyr A3 (old sabre defense) with a 1x4x24 MTAC scope. This gun made me look like a hero at my local gun range. I am not some great marksman. That being said I shot super tight groups at 100 yards. Even with a hot barrel the POA didn't shift.
I highly recommend buying an AUG.

I also was lucky enough to buy a A3 CQC from PJ. It's still NIB and will stay that way. I'm having too much fun tack driving with my old sabre defense A3.

Only complaint is I have had trouble with a cheap steel case getting stuck in the chamber. From now on I only shoot brass case ammo.