I've got a 7.5" blackout pistol with a kak blade, Troy Claymore muzzle brake, and a Fostech Echo trigger . I thought it would be a bit hard to control (especially in echo mode) but truth be told, it's not too bad. Just lean forward and hold on tight. Recoil isn't bad. My 8 year old can shoot it in semi comfortably.
If you want to use a can, many mfg's say no shorter than 10.5 inch barrel for the .223. The can makes the AR pistol nicely doable for home defense. Otherwise I can't imagine shooting the thing indoors with the possibility of no hearing protection. A piston upper, such as Adam Arms, is also desirable if you suppress the AR, otherwise gas blow back with direct impingement is annoying.
Make your own gas buster charging handle with some gasket seal / high heat RTV. Makes a huge difference on a DI gun. Many tutorials out there on how to do it. Do a handful at a time to save time.
I'd almost forgotten what gas-to-the-face was like until a few weeks back I was playing with the BFSIII on a shorty with a can, but did not have a DIY gas buster on it. GAH! Holy patties, batman...seriously, makes that much difference.
I did the charging handle "gas buster" mod on mine as well, both piston and regular. Of course it's more needed on the direct impingement guns. In either case, as the bullet departs the gun, there's still high pressure in the can to bleed off. That gas, with all the combustion crud, goes both ways, out the can muzzle as well as right back down the barrel to do the gas face thing. It really isn't at all bad on a piston gun, which is why my suppressed AR's are piston.
I installed a Franklin binary trigger in my 9mm CMMG which uses the COLT SMG magazines. The 9mm with the binary trigger makes double taps very easy. It reminds me of my former agency issued H&K MP-5.
The only weapons system that I prefer over an AR pistol is one of my Steyr AUG bullpup rifles. Because of their bullpup design, they are virtually the same length as an AR pistol, but have a full length 16 inch barrel.
I feel similarly about AR pistols, since I am a fan of bullpup rifles also. Between the PS90, the RDB, and the RFB, I've never had much interest in an AR pistol from a technical standpoint, except for the existence of the binary triggers which are not available on the bullpups. From a legal standpoint, the concealability of the AR pistol is nice though.