Stock slash goes 40 mph with incl NIMH battery....It seems like running 3S lipo batteries causes heat issues. Running 2S lipo batteries, the truck also goes 40mph. Is there an advantage to running 2S lipos or why not just use the NIMH battery? Also maxx amps has a 8 or 9 cell NIMH battery that will push the truck to 60mph. Will that cause heat issues?