I like the 2.5R better than the 3.3R. I have seen way too many broken connecting rods in 3.3s but I have only seen one in a 2.5. Mostly I hate the carbs but I can make them work. I have a 15Pro in one of my RC10GT2s and its adequate, the other two have an OS12TR and a Hobbyking 15. My 1/8 scale buggy is an Ofna Hyper7 with a stock .28.