In the not too distant future I'm thinking of having Dave over at MRD perfomance make a full system exhaust for the YZ450 I'm getting myself for Christmas. His full systems are $400 and are supposedly some of the best systems out there especially given their price. When I called to find out more about his products he asked which type of head pipe I'd want. He will custom make the header depending upon where you want to see the most increase in power. He can give one head pipe that will greatly increase low end to mid range or one that will focus more increase in the mid to top end range. Gains will be felt throughout but the biggest increases willl be in those ranges depending upon the chosen header. I haven't taken possession of my bike yet which is why I'm holding off to order the new pipe but it got me curious as to what most people have or would choose. I'd like to do kind of a poll to find out: 1. Where people feel the '06 YZ450F could most use an increase in power. 2. And what type of riding you do (mx track, sx track, tight trails, wide open desert, etc.) to justify where you'd like to see more power. I don't want this to turn into a "which exhaust is best" thread as there are tons of those. Which pipe brand isn't as important as where people feel the YZ450 already has more than enough power and where it could use more. I'm not sure if many other companies customize the head pipe to where you want the power or not.