These engines a screamers!! Plain and simple..... I race truggy and buggy and I have B5's in both and they are super quick on top and bottom,reliable and run cool. They never let me down in any race. I have had tried so many engines and the B5'S are awesome! I can not say one bad thing about them. For $200 you will NOT find better engine and even if you spend $300+ dollars the B5's are just as fast. I have 1 Vspec,2 sirio cl7b sti's, a plus 4 nova ,sirio extech2 .21 and a sirio extech2 .24 sitting on my shelf in my closet. And I can truly say they are all fast but powerband and reliability and cost the Werks is where it is at.......... for the price of a nova piston and sleeve you can just buy a whole new B5! lol lol.....