I just picked up a P320 Carry to add to the Sig collection (P226, P229, & P220).

I was looking for night sites and the compact model, but the local gunshop only had a Carry model with night sites, so I opted for that.  I figure I'll just get a sub-compact grip module for CC and do a backup 17rd mag.  I do plan on picking up one of the Romeo models, so this will just cut down on the different mags I'd have to pick up.

I have a comp and the full size 320 in 9 mil  they have been flawless. The dealers around here are having trouble getting them in right now some told me .

I've been thinking on a 320 Carry since Grey Guns released his flat trigger

I have the 9mm Carry.  So far I don't think I'll bother with the compact grip module.  The pistol seems to conceal well enough with the longer grip.  The difference in size is a quarter of an inch.

Mine started out as a Carry model.  I found a used tan Compact grip frame and after I tried that I sold the Carry frame.  The Carry only holds one more round than the Compact, so it seemed a little silly to keep both.

Congrats OP.
I started with the full size and then purchased the carry conversion kit.
My next one will be the Romeo also.

Which caliber? My 9 compact magazines are 15 rd and the full size/carry mags hold 17.

The Carry and Full size only hold one more round of .40/.357 than does the Compact.  Even for two rounds I'd prefer the compact; it fits my hand better.

I picked up the 9mm, so 17rd mags.  I was mainly interested in the night sites and the only model the dealer had was the carry.  Originally, I was thinking the compact.  

Regardless, I'm happy with the purchase. :D  

I did manage to find the sub-compact frame and mags (both in the sub-compact and more full-size) in-stock online.  Should have everything by Monday next week. Options never hurt.

What grip width is the default? Small or medium?

Or does sig ship various grip sizes on various p320s?

The full size, carry and compacts come standard with a medium grip. I think the subcompact comes in small.

A P320 in 9mm is on my short list. I need to find a (full size, carry, compact) near me to shoot and see what size works best, I have big hands and don't like sub-compacts. If I need a small gun, I'll get a Bond Arms derringer. I have an old S&W 459 9mm that I most likely will sell or trade, it was my first pistol I picked up used in 1990 or 91.

The Carry is essentially a compact slide on full size frame (with shortened dust cover).
So decide on barrel length Full or Compact then mag capacity... full size 17rds (full and carry) vs  15rds compact.

I picked up a P320 Carry used not too long ago.  It is the first striker fired polymer framed gun that I actually like enough to want to carry.  I picked up a subcompact frame and a couple of the 12 rounders, but I keep going back to the carry frame and 17rd mags... it's basically the same size as my CZ P-02 that I carry daily.
The P320 may displace the CZ as the CZ is basically a unicorn and I can't replace it if it gets taken into evidence after a shooting or damaged.

Mine has the Apex flat trigger in it.  I continue to believe that Apex makes good stuff.  They've made my various M&P pistols tolerable to decent and made my little J-Frame downright nice to shoot.

I got the sub-compact grip without the rail.  There's a little moon-shaped gap in the front dust-cover where the grip doesn't cover it.  Kinda disappointed about that, but otherwise I like the grip for carry.  Still need to get out to shoot it.  Weather hasn't been nice and there aren't any indoor ranges close.  But soon.

On a different note, I found a Tacops for $600 in EE and picked up too.  

So I have 2 320s now.

Nice score on the TACOPS.