I run the extech and i love it its a beast to say the least and i finally thinks its broken in cause now it will idle all day long! I also have run Rb engines in the past and they are great as well. I have also hear that the C6BB did not Dyno well? These dynos are crap compared to track time and expierence! I know my extech has plenty of bottom and pulls the straight just as fast as any engines where I race and its not the modded one! Just like when i ran the C6BB it was always one of the beasts at any track I went too. The dynos are not a accurate way to rate engines!