Ive had a lot of fun with a MechTech upper in 10mm. It crushes pistol plates and dueling trees at distances which I’m less accurate with a pistol
I have the Mech Tech carbine in 10mm also and it is deadly accurate with jacketed bullets but not so much with my home cast lead bullets. Now my home cast bullets work very well in my handguns but the extra length of the barrel in the carbine apparently rasies the velocity to the point where it must be stripping the lead bullets. I need to recover one of the lead bullets undamaged to verify that, that is what is happening. I put a red dot sight on it and it is a quick and accurate little carbine.
On another note, did you know that .45 auto magazines work just as well with 10mm ammo, at least mine do.