They are both great weapons! The M57 is a single action that shoots the 7.62x28 round, the one that has been demonstrated to penetrate everything. It is very accurate, but hard to justify for home defense because it does penetrate everything like walls. I is the one handgun round that will pop through a Kevlar helmet. They fit your hand very well, very slim, and well machined. They are accurate and cheap to shoot with surplus ammo. The CZ82 is a definite winner. It has a great trigger, both double and single action. The sites are small, but it's very accurate and fun to shoot. fits your hand very well and the added weight of an all steel gun takes a lot of the shock out of the 9mm Mak round. They seem to last forever.
As an asside, I was talking to a guy in Minnesota who started selling guns last year though hes in his 70s in partnership with his gunsmith. They located a deal where they could buy these guns in lots of 10 and get the M57s for around $136 and the CZ82s for about $146. He may have been lying to me or fibbing, but since a lot of the dealers on line are selling them for around $200, I think it is probably true as a markup. Check it out. You can get your own and make some money as well since you will have the FFL. Good luck and keep us posted.