Trustfires and NiMhs do NOT provide enough current for any of these motors. Even the RM2s.
The RM2s should probably only be run on a 1s system.
But torukmakto did some FPS tests, these don't seem to be any better than stock anyway. Duke_W has seen the same reports I have.
If you do use Plasma Dashes with the right batteries, you will need a better switching system. I haven't gotten to using a relay system yet. Will soon, after some robotics projects are done.
1. The RM2 motor specs for 6v so you're giving patently false info about that.
2. I did measure fps using a ballistics chronograph and they definitely are stronger then the stock motors, volt for volt. Compare apples to apples.