Hi ton i had the Metal Mule 2 in 1 exhaust fitted, �350 agaisnt ��� for OTR, you will find most after market exhausts are a fair bit louder than std even with baffles in place, not so much when running, but popping on the over run!! I had satisfactory fueling with the Kev Mod but a PC is a better option. Check out www.bikehigh.com

The hepco and becker frames are strong enougth! in a hard crash if the frames are too solid something has to give, rather the frames than the sub frame! Have read on other forums the small problem with hepco and becker boxes are the mounting system they use to fix the boxes to the frames. Its a good quick release system but can become unrepairably mangled in a hard crash. Would keep the frames but swap your box mounts if possible to Touratech box mounting 'pucks' which are available separately and are more robust.
Then again if you dont plan to crash too hard....

Ps drawings done, i just got to work out my scanner!