Aside from ammo availability/pricing, would you share you thoughts on why?
Cause I'm a troll
Because it's an M1 and they aren't being imported right now (though we had a thread here recently where supposedly they will begin importation again in 2014). For that reason and the fact that I think 9mm is enough to handle most things on two legs, I wouldn't swap one for the other. I'd try and save up for the G20.