I owned a 16 foot C-Dory. Now I own a Cape Cruiser Venture 23 (made by the now defunct Cape Cruiser Company, not by C-Dory). I loved my C-Dory and I love my Cape Cruiser. I've been from Olympia, Washington to Petersburg, Alaska and back in the Cape Cruiser. I've had no problems of any sort with the hull. Les Lampman is working on a couple of little things for me at the moment - like figuring out how not to leave quite so much gas untouched in the bottom of the tanks, but I really have nothing but good things to say about the boat. If you're getting an "original," i.e., pre-C-Dory Venture, and are concerned about warranty coverage, I'd try to get something in writing.
When Cape Cruiser went out of business, I was contacted by the owners and told they would stand behind the boat. With the experience I've had, I'm really not concerned I'll ever have to find out just what that means. I'm a realist. You can't squeeze blood out of a turnip.
Best of luck with your decision.