stryfe imr questions?

What's up everyone. Finally got a new stryfe and had some questions on imr batteries.

First off, how many imr batteries can I safely run in a stock internal (for now) stryfe?

I'm almost certain 2 imr's and 2 dummie batteries would be completely safe in a stock stryfe. But, I have seen/read that bypassing the thermistor will allow the stryfe to run on 3 imr's and 1 dummie without shutting off to protect itself, but is it safe to run 3 without damaging my stryfe?

Eventually I will replace motors, cage, flywheels, rewire etc, but can I run 3 imr batteries with just bypassing the thermistor and removing locks without killing my stryfe?

Also, which 14500 button top imr batteries should I buy? (Don't plan on going lipo)

Efest red? Efest purple? Some other brand of imr battery? Should I be looking for some kind of "protected" imr?

So, which imr batteries, and how many imr's can I safely run on a stock (for now) without destroying it?

Thanks everyone!