If I remember correctly, the SOCOM block is to allow the use of unmodified sten mags in the Oly conversion, not the Colt-style.
I have the first complete RRA 9mm to go out the door commercially a little over a month and a half ago. Flattop with mid-length free float tubular forearm. I've got about 600rds through it at this point without failure, althogh all I've tried is differing weights of ball ammo. It uses a 9mm hammer, a Colt-style mag adaptor, and in my case (using with a post ban, A2 stock) required a 9mm heavy buffer, CAR spring, and a delrin buffer insert to account for the different lengths of the buffers.
I have fired with both 25rd and 32rd (modified) Uzi mags. The primary conversion is slotting the side to accomodate the mag release, and opening up the back of the mag at the top to allow the bolt to pick up rounds off the carrier and clear the mag adaptor. It has the gas deflector and short port door.
It is available in both pre and post ban configurations, either flat-top or A2, with CAR or mid-length handguards (either standard or tubular), 16" only (1-in-10 twist), no gas tube as it's blowback operated.
I'll try to answer any questions if you have them.