[Finnster]

Its kinda hard to say Dave, but the is a huge difference in the feel between the XLs and a Neu. There is so much more TQ that the Neu can just make the truck zing when I want it to, where the XLs needed a bit more run-up.

You may just end up driving faster w/ the greater power and end up in the same place. But, as a very very rough estimate... if an XL is 70% eff, and a Neu (on 4S) is ~91 (call it 90%)

Then .9/.7=1.28 or so. Ie giving you 28% more runtime, if you drove the same spd. IDK the exact eff #'s of the XLs, they are not rated, but just a # I've quoted seen before . If they are 80%, then not as big of a gain.

You may be hard pressed to make 15min on 4900mah. You may need to just go upto ~6000 if that is the end-goal, and may be cheaper than trying to pinch that much out thru eff gains. The Neus do rock tho