I had it on my 15 RS for 14 month and it does show discoloration but should have many miles left in it.
I installed a thumb screw to act as a baffle for better low end response but I suppose you can take it out if you like and replace with bolt/nut.
$120 shipped in 48 states or $100, if you can pick up in Las Vegas or Los Angeles or anywhere in between the 2 cities.