I've had a Mustang on two of my Harleys and on the Vulcan Nomad I now own. I agree that they are the best bang for the buck. I don't see a slot for a backrest on yours. Does it have one?
Also, that appears to be a nice looking tour pack.
Best bang for the buck.. I've tried a lot of seats in my riding days and have to say the Mustang seat is my favorite. I bought mine back in 2001 for my RK and it still holds up well and is as comfortable as the day i bought it. I visited the Mustang plant in Western Massachusetts it's a nice set up they have out there. A little disappointed when i found out they just make the seat for the Rocket Touring model though... Looks great on your bike..
I had a Mustang seat on my 2013 Triumph Storm and loved it too...shame they dont make one for the Roadster or would have one!
The Roadster is wider in the frame than the Tourer.
No 1st hand experience with them, but this place (see below Contact Us) seems to have a pretty good rep according to the Harley site guys. They mod the seat you have. Might be worth a try for the Roadster??
I got @canecorso to custom make my seat,I only wanted lower back support,he did a great job, the stock seat was killing me. Any pillions that have got on the back are quite comfortable as well.