Bronson I also felt the backrest pushed me a little too forward, so I ordered the offset (wish I'd ordered with the seats) and it did make a difference for me.
PapaTom - Did you have any interference problems with the offset post and the passenger seat on your Mustang? The MustangSeats web site let me to believe that it only worked with seats with the reinforce concave front. I had the Mustant seat with the riders backrest on my VStar and we loved it until I used the backrest. I had to manufacture my own offset post out of 1" x 1/4" steel strap. I was going to order a new seat for my RoadStar last night but I wanted to get your feedback on this first.
My bike is in the shop for two weeks. Yamaha authorized them to tear it down and swap parts to resolve the excessive engine noise issue. They say they've had good results doing this in the past so I'm encouraged. Only problem is, "What am I going to do without my bike for the next two weeks?".