ok ive been out of the hobby for ten years, but randomly i bought a summit a week ago, then two days ago a slash, so my Q. is should i up grade it to brushless? is it worth the money and is it that big of a diffrence? and if i go brushless should i cont. using nihm batt. or go lipo and why? and one more Q. i deff wana upgrade the slash should i just leave the summit alone? the 775 seems strong?