Ruger is selling its excellent 57 pistol (in the 5.7 x 28 cartridge) as fast as they can make them. I haven't seen RUGERs go this fast since the Precision Rifle was first introduced. SO... perhaps by this time next year RUGER will make the PC carbine in 5.7 x 28. It will certainly be less $$ than the FN PS90 carbine. And it should not take a lot of re-tooling to make the PC Carbine in the FN cartridge. The bolt will have to move a bit further to handle the 5/7 cartridge but perhaps only 1/4" more at the most. Naturally it will take the 20 round pistol magazine. If it sells well you may see 30 or even 50 round aftermarket magazines. AND maybe more ammo companies will begin making 5/7 ammo and the prices will finally come down. It would sure be an excellent PDW for home. Eric B.