Well, where do you plan to run? Do you have a dirt lot to run on? Cuz tenth scale isn't so good on grass. That's where your eighth scale nitro had the advantage. With tenth scale you're going to want fatter tires and you will want to gear down so as not to overheat the motor. That's the standard answer. What sort of vehicle excites you? Still have the short course truck? What's your budget? I'd look at truggies. Fatter tires, three diffs, fast. Kits might be difficult to find. I love my HoBao Hyper TT truggy. Available as a "80% kit" for $200 it comes mostly assembled, minus electronics, and a clear you-paint-it body. You install the ESC, motor, and receiver of your choice. I'm running a Castle 4-pole 5700kv motor and 120Amp ESC. Running on 2S LiPo. Love it. Its weak points? Not many. Mainly, it needs a good aftermarket bumper set. T-Bone Racing makes a front and rear set that really protect the car. I also installed the aluminum front upper plate and aluminum steering knuckles and aluminum steering rack.