I'm kinda confused about the runtimes I read here.. My track is closed for winter and won't open until march or april, so I have no chance to run my sc10 4x4 yet. However, my slash 4x4 (and 2WD for that matter) on that track (small-medium sized, astroturf), using stock VXL setup, easily ran 20-25 mins on a 5000 mAh LiPo. Do the 550 sized motors eat up that much more power or why the large difference?