Originally Posted by Davidka

Brushless isn't any harder on diffs than brushed motors were. Ever since 2000mah cells started being used in modified, the limit to how much power we run has been traction, not motors or batteries. Aside from the growth of carpet racing, power and traction haven't changed for 15 or more years.

A properly built ball diff with a properly set slipper protecting it lasts a very long time. It has the advantage that its action doesn't change under load. This is why they're still the best on 2wd buggies on dirt.