I took delivery of a new canvas cover from Fairclough Sailmakers the other day, and I have to say it is a thing of beauty. They aren't cheap, but I plan on keeping my boat for the long-haul and this looks like it is built to last. Compared to shrink wrapping, it won't take too long to pay for itself, and the guys at the company were great to deal with also (thanks Erik!).
If you are looking for a winter cover, I would happily recommend these guys. Definitely a case of you get what you pay for. And no, I have no interest in the company -- just a happy customer.