i am not a fan of kel-tec. when i got my first sub-2000, it seemed like a lot of plastic...but i figured that they made em this way ...they must be ok.
was i wrong, blew mine up...fired from an open battery position..destroyed hinge, and front receiver housing...but i must say, it blew up safely...mag hit the ground..gasses out side. a few weeks later my buddy blew his up same way....
as i said...way too much plastic, really cool gun..but receiver shoud definitly be metal....but keltec has an awesome warrany, replaced ...no questions asked.
i like the idea of the SU .223......but i'm how they say.......a little gunshy