I had the Bushmaster Shorty AK.
I suggest firing one before you buy if possible.
It was way, way too loud for my tastes.
And, I never liked the idea of losing 2" worth of velocity for a muzzle brake that is absolutely not needed on a .223 caliber weapon.
Sold my AK upper and got the Bushmaster M4 profile 16" upper.
Now I have the shortest barrel allowed by law, it is 1 lb lighter than before, not giving up any velocity, and the lower db level without the muzzle brake makes it much more pleasant to shoot.
Oh, by the way, with either upper, never any jams or problems. (Except when using a USA magazine.)
Bushmaster all the way.