So I just got back from the MI Bike show. Got into a discussion about different exhaust systems for the new girl. And after hearing so much from mostly everyone ... you know everyone who had heard from someone else, even most friends who work at the shops around town, I've been backing the Graves name. At the bike show though I found a person who disagreed with my Graves "preferance". What he was telling me made alot of sense. So in saying that I would have to say don't sell out to the Graves name even though they produce a good system. Just keep in mind that each bike just like each pipe produces different output horsepower. Why else would we dyno. Anyway always keep you're options open.
not that this answered you're initial question but just some input.