I have the new Losi box with a lipo and it had no problem with my OS .28, but I do pre heat my motor, not for saving a bump box but for adding life to the motor. I had 2 chrome top ofna boxes when i ran my SC8 and my MBX-6. Yes they have good power but heavy and a pain to get everything to line up. Losi just works, period. One box for both truggy and buggy.