Went to the range yesterday.
Tried it with a full mag on a closed bolt (loaded chamber) and open bolt - no bolt over base issues or function problems. Weight is similiar as a steel H&K magazine.
Only problem is sometimes loading it one round at a time, it seems that the case can seat itself in the groove at the back of the magazine and keep the following rounds from loading staggerd. Loading it from the top is no problem, just like a normal one.
I have a Dept rifle class comming up in Oct, I will give it to one of the guys to abuse.