Sup dude,
Their's been a plehtora of comparisons here...
If you like to actually build your RC's like many.....eerr some..lol then I would definitley go with the SS and then get the 3 shoe clutch and the new gastank (even better get the 4 shoe clutch from UE and the other stuff you need to run it). Their is some other sweet stuff on the RTR but offhand I'm brainfarting on them.
My Savage .25 RTR should be here any day now from Tower but I definitely would have bought the SS kit if I had the time to build it. Lately I've been lucky if I even get to romp my maxx for an hour much less build one.
BTW....THe savage .25 RTR also has a composite, dual chamber pipe as opposed to the polished alluminum ribbed pipe on the SS!!!
Peace