My next door neighbor has the Cycle Shell for his Ultra.
I bought the Bike Barn for my RKC.
TheBikeBarn It's the same principal, but slightly different. The Cycle Shell is very portable, and seals at the bottom better than the Bike Barn. However, the bike barn is very durable and has more room inside. While away for two weeks, we had a very wet snow. It was weighted down hard, but didn't present a problem. It's repelled a few hail storms here in TN recently too, without any problems.
It cost slightly less than cycle shell. I think either of the two are great products. Check it out at
www.thebikebarn.net
Covers are great, but with the Bike Barn you can drive in and close it shut no matter how hot the bike is...nothing touches.