dom, I have the Hyper ST and yes the engine is a paper weight now!! it has a Axial in it now and the thing is a whole new truck. I also have 2 thunder tigers at my disposal and have to say they are nice trucks as well not as refined as the Hyper but every bit as tough and the engine is wonderful!! if your bashing Id have to say TT ST1 as for racing Id say Hyper ST. hope this helps