My problem is specifically with the Dual Tour seat on the Rocket. The main problem is that instead of using the existing key quick release the seat bolts on, worse, the bolts are not accessible if you have Corbin Beetle Bags. To access the battery I had to remove both bags, then the seat that is held on by 2 bolts.
Other minor problems with the seat is that the stitching lets in water, if the seat gets wet, you'll have a wet arse for the rest of the week and its thicker than the stock seat, so you'd better have long legs or a landingear Legup.
The fact that the stock seat has channels leading to the airbox and the Corbin did not did concern me, but I dont think caused any problems.
That said, I'd not exclaim Corbin sucked because of that alone. It is the very poor quality paintwork, build, ergonomics and slow unhelpful (but polite) customer service that brought me to post.
I'm still waiting for my 3rd set of Beetle Bags that the dealership removed June 2009. I would expect a reputable company to be embarrassed by the same paint problem on 2 sets of bags and to want to get them back to me promptly. These things were expensive and not nearly as good build quality as the Triumph Tourer ones.