+1 on the weight issue. My stock header is a hell of a lot heavier than my mjs header. The majority of the weight IS in the cat. I lost at least 10lbs and you can really feel the difference. A full system header is not all that much lighter than a modded header w/ a midpipe. And if your bike is tuned right, the gains will be significant, for those of you who really care about numbers. How many people here can honestly say they ride well enough to be able to really use the added hp?? That they're not getting all they can out of their bikes unless they get the top of the line exhaust system. Don't get me wrong, these top, name brand aftermarket full systems are nice and proven to be efficient, and if you got a lot of extra cash, hell, go for it!! Personally, I'd rather get a nice, decent setup and spend more money on tracktime. But that's just me. I don't need the sweetest, shiniest, full system so I can say "Look at me, I have a Leo Vince or Akrapovic full system on my bike and I'm gettin XXX hp to the wheel!!" F all that. Get out and ride!!!!!! :FU