Hey guys I am in the process of shopping for a muffler for my australian 2000 wr 400. I can get hold of a yz 400 muffler for half the price of any of the good reputable aftermarket mufflers available in australia. Has anyone tried a yz muffler on a wr, and are there any mods to make it line up to mounting points etc.? How well do the yz mufflers perform compared to the staintunes/barrett/w.bros etc. etc. ? Any words of wisdom or advice is much appreciated. I would rather pay half price if the performance is all a much of a muchness. thanks dudes!