I am running a
Softopper on my S-series crew cab. I really like it. They show having one for all years of the Silverado. You will have to specify the bed length when choosing. Looks like the price range is $630-$670
I found mine slightly used at a very good price. Once you know what model number you need you can watch for them. I ended picking up a second top for mine and have it in the garage. The price was just too good to pass up. I am kind of holding on to it until a friend decides it is the way to go for him.
They do not support a roof rack like the Canback. I don't have that need though. The quality and fit is good. I have had mine on full time since October of last year. No complaints.
Check out their gallery
Softopper customer gallery I see a couple late model Chevys with Softoppers in there.