I've started looking at short barrel shotguns.  Seems you can find the Benelli M1 Super 90 used for a hundred or two more than a new Mossberg 590a1 52689(ghost ring model).   What's the hives opinion?  Which should I get?  Looking at keeping it under $1500 w/stamp.  Anything else I should be looking at?  

Love my M1S90

Same here. The Benelli M1 Entry is basically the perfect tactical shotgun. Lightweight, handy, reliable, accurate, great sights. There were 2 factory sights: low-profile rifle (both on barrel) and ghost ring. I prefer low-profile, due to anti-snag.



You'll be able to "ghost load" the M1, which is having an extra shell resting on top of the carrier. Doing this, it will hold 7 shells including a chambered one. This does not affect reliability one bit.



There's nothing wrong with a 590 either, but I think it's worth the difference in cost to have a semi-auto.



Get a Surefire dedicated fore end light for either, and you'll be all set!



M4's are expensive and designed for hanging heavy objects onto them. You don't need that...

Build your own.

Reasons:

1. EFILE - 1 month approval or less
2. Cost, its cheaper

Wow, that's an apples / oranges comparison.

I have owned an M1 (not SBS) and it is a fine shotgun. The entry M1 would be pretty awesome. I'm not sure where you got the idea that a 590A1 with stamp will come anywhere close to $1500 though. I have one with a bead sight in jail waiting for the stamp. It was $520 so you can do the math.

I prefer the bead for a defensive shotgun and have a lot of experience shooting steel at 7-10 yards with one. I know the GRS or rifle sights are better for slugs at 75-100 yards, but that is not the main purpose of my SBS. The Mossy model you show has a 14" LOP stock which is way too long for most shooters and I would have to change it out. This is more easily accomplished with the Mossberg. The 590A1 is easily outfitted with a Magpul SGA stock which is the best tactical shotgun upgrade I have ever used. The SGA forend can be fitted to the 590A1 but it takes some modification. The Hogue youth stock also gives a shorter length of pull for less cost but the Magpul is adjustable between 12-14" and is truly awesome. The Benelli stock can be shortened but it takes some custom work (info available on the Internet).

The factory GRS Mossy may not be as easy to find as the bead sighted model so if you must have GRS (or want a semi-auto), the Benelli may be your best choice. For my money, the bead sighted factory Mossy SBS is the best SBS value there is.

M1 entry is one shotgun I would love to have, great looking.

I'd love to put a 13/14" bbl on my M1S90. I have the regular riot/bead bbl with extention, PG stock,  as well as the field stock and hunting bbl and every choke made. Bases pretty covered. Still, the entry bbl is one sexy piece of tube.

dang double post problem.