I had one of the Erma Lugers for a couple of years. The trouble I had was that, while the gun looked good, a lot of the internal parts had been worn out, except for the barrel. I ended up replacing most of the parts and gave up when it came to getting a new magazine (the feed lips were badly worn). When it worked, it was great fun and would still shoot a decent group. And it convinced my wife of the reason for having .22's (she thought that the only reason to have a gun would be for self-defense, but she enjoyed the .22 immensely so saw the fun potential).
So, on an Erma, make sure you can check the internal parts for wear and check the magazine feed lips for wear. I did shoot some CCI mini-mags in it, but not enough to know how it would stand up to long term use with them.
Mine was a great learning experience - it was only the third gun I'd ever bought and I knew nothing about getting and installing parts back then; now, I'd buy the parts from Numrich and do all of the work myself instead of paying a gunsmith.
I traded it and a little bit of cash for a lightly-used H&R Sportsman 999, which I still own and love to shoot.
