personally, if i had a Nitro Evader, I'd never upgrade the engine. I have a .12 in my GT for racin', so i'd just stick with the old DTX 18. IMHO the best RTR ST engine on the market, and I'll say that until RTR ST's come with a .12 CV-R and a starter box
but, i wouldn't replace the DTX18 with anything but a .12-and that'd be for racin'.