I have no experience with the TMaxx, but I do have a savage. The .21 Nitro Star was very easy to tune. After about 3 tanks of fuel, I was running wide open.

The main problems I have had with the engine (and I read a lot of other people do also) is the pull start broke after about a week, the engine plate under the pull start came loose, and the One Way Bearing went bad.

None of these were a big deal though because I bought the Roto-Start and used LocTite on all the screws in the engine. I am still waiting on the one way bearing to come in the mail, but in the mean time I am trying to figure out some way to keep oil from getting on the shaft that the one way sits on. I have heard of some mods people have made to alleviate the oil problem, but I'm not sure how to handle this yet.

You will be happy with the Savage, the engine is very good, and I've heard lots of complaints with the TMaxx engine.