i think they have a good mix of old and new parts. rpm suspension etc still usable. transmission, steering, chassis, diffs upgraded.
thats more or less exactly what i thought. i was very near to buy a t maxx 2.5r and convert it to a single speed lightweight plastic e maxx. but now i think this strategy has become just useless.
I see they upgraded the diffs but it still looks like they are using the old style bulk heads. If they are then i think they would have to use different diff cases.