Yep Bl on nimh will be faster than Brushed on nimh but you may wanna up the voltage on your packs to enjoy BL power more.
also motor maintaince will be near zero upto brushed as low turn brushed motor wear out a lot quicker than higher tum motors,we all know lipos discharge higher than nimh blah blah blah
But im running 8cell packs on BL and getting 50+ on an MT

if you do choose to go nimh my advise is get GOOD quality cells on BL setups