only changed the headunit, kept Bose speakers and amps. sound is ok, not an audiophile myself
you might need to get some in line boosters, because on some headunits the volume levels drop, but it's something that can be added later if needed.
For steeping wheel controls I phoned ICT directly, because at the time ICT released an updated cable which Sextons didn't have.
Also worth mentioning that Sextons sent me the wrong fasia, but ICT Direct did.
If the GPS setup is the same as the F900BT, then pick a good spot for the signal receiver, mine is under the triple gauges.
Anything else just ask, if I don't know, I'm sure somebody else will