Li-Ion Power Tool cells work great for RC!

[squeeforever]

Brian, I run a 10XL on my E-Revo (setup to race) and I think or racing, 4S would be PERFECT. 15C should be plenty for this motor as well although i would personally go for a 2P setup. With the M1 cells a 2P setup will get you over 30 minutes of runtime I believe. It just depends on driving style. I've still only got 4 runs on my new IB4200s and they kept getting 5 minutes more every time. My last run was about 23 minutes of really hard running.