Is silent choice affected by the Imco Xtreme Advantage 2" shorty?

How does it work compared to stock XR lower, and what are the limitations? lower max rpm in silent mode etc?
I have never run mine above 3500rpm

Imco's website says: "Redesigned internal exhaust passage is more efficient"
Sounds like there may have been issues before.

Anything else to watch out for in this swap?

You should have no problems at all. I installed an Imco -2 on my Fountain and it was no problem at all.

Thanks man....