Hi.I've got an MMM'd summit.Great truck

. It's better off road than my 3.3 maxx,Flows over lumps and holes.Jumps really well,is tough,I've only broken the T lock servos(before I knew how to adjust 'em) and 3 front A arms,40 mph + tree = broken,same with a lump of rock hidden in long grass

.People were worried about the T lock diffs crapping out,they're fine as long as they're not locked/unlocked when travelling at speed,same internals as the revo vxl except the lockers. Mines fallen off a 40 feet drop in a local quarry,only creased the shell

.The stock tyres are good for crawling,not good for 40+ mph,uncontrollable springs to mind.Have a look on the traxxas site.