Dansi:
From my 1 year experience with Cosmic C, one can't talk about ride without mentioning trim tabs. I think they are absolutely mandatory on a CDory. On the St Lawrence river, where a short sharp chop is very common, Cosmic C (25' cruiser) would either be very slow or very uncomfortable without trim tabs. With them it is neither. I can cruise comfortably at 15 - 20 knots in a chop which, without the trim tabs, would take the fillings out of my teeth if I exceeded 10 knots. I am also convinced that properly adjusted trim tabs actually increase the already great efficiency of the boat.
We did 1300 miles last summer, including 750 miles from the Chesapeak to the St. Lawrence. On that trip, which we had to do quickly for various reasons, we averaged 15 knots as measured by the gps (this includes waiting for locks and locking through) and nearly 3 mpg. We were never uncomfortable (except on Lake Oneida in very steep six footers, but that's another story). I don't think we could have done it like that without the trim tabs.
And make sure you get properly sized tabs. Cosmic C came from the factory with grossly undersized tabs (according to the recommendations of all major tab suppliers), and I refused to accept it until properly sized tabs were installed (at no cost to me).
You'll love your CDory, but with trim tabs you'll love it a little bit more!
Pat