Has anyone had any experience with the "power bomb" type header pipes on a 09 WR250F. You know the ones with the bulge in the middle. Either GYTR or other. Are they worth the investment ? Do they add power ? What kind of power do they add ? I've already put on a GYTR tail piece and done all the other free mods. Bike runs pretty well but if power bomb significantly improves performance I'm in. Any feedback would be greatly appreciated.