I put on my ATS arch flow manifold last night and this is what I've noticed. I have a 04 305/555<-- "well used to be", 6 speed transmission and have always had a little studder when I'm taking off, until the turbo really starts to spool. I was hoping the Bully Dog Power Pup was going to get rid off that, but it didn't. Last night, right out of the driveway it took off, no studder and smooth as glass. Seat of the paints is great! I bought it from Industrail Injection and they sent me a polished manifold and it looks great sitting there with my AEM Brute Force intake... Is it worth the money? I'd say hell yeah, as smooth as it runs now, I couldn't be happier. :-laf