TRUEBLUEMAX
My 2 cents is to go for the RS5 vs RS3 if you are going Yoshi. Its quite a bit smaller, easy to install, and has 2 sweet sounds: one loud and one not so when using the insert. I have the RS5 oval outlet muffler and midpipe off a CBR600RR (you use the midpipe to fabricate the "S" pipe you need to center the muffler.
I use the RS5 with the low volume insert installed in the muffler 90% of the time. Its easily installed/removed with an allen key and needle nose pliers.
IMHO, it is about the same "helmet loudness" as the Skinz Ultra Q (which I had before the yoshi), but I find the sound a bit easier on the ears....and for full disclosure I've used earplugs on my sleds for 20 years, but occasionally without and its still not bothersome.
Besides, anything is better than the 14lb stock boat anchor.....
Good luck,
OTM