I have had to put a piece of large fuel tubing over both the low and high end needles. The low-end will creap out, as you have seen causing poor performance, and the high-end needle creaps out and leaks air. Fuel tubing fixes it up pretty well.

I have 2 rock solid Mag 15's, one pretty decent and a recently purchased one that will shake your fillings out, if you try to adjust the needle. It vibrates so bad, I can't keep mufflers on it, may need to send it back, just haven't.

With all that said, I'd fly combat with you guys, no matter what you brought!