Man, you NFA guys get to have all of the fun. Beyond my $ limit but we were able to fire my friends Mac 10 yesterday. What a blast. It is configured in a short barreled rifle configuration and we found it very controllable using 2 and 3 round bursts. He even dumped a full mag at 20' and kept them all on target.
We had several jambs but I think they were all magazine related. Most of the magazines were 50 years old. We separated out the ones that jammed and all seemed well. He did try a couple of my hand loads and they worked fine. Overall a really good day. It's amazing how quick 500 round of .45 evaporated. Here is a video of my 18 year old daughter firing.
http://www.flickr.com/photos/6032394...in/photostream
Wish I had the money to join this club. Heck, even my wife enjoyed firing full auto.