CD25 the good and the bad
I owned a 1975 CD25 a few years ago. I was very pleased with its sailing ability. It handled big winds and the short, steep chop in Pamlico Sound well. It is small enough that I could single-hand it easily.
My boat had a problem common to many CD25s. The decks just outboard of the cockpit sagged due to lack of support directly under the companionway. This would cause water to pool up outside of the coamings instead of draining. There was always algae growth to clean up and the toerails were starting to rot due to the perpetually wet decks. I've heard of some owners fixing the problem by jacking up the sagging areas and adding supports.
There were really just two issues that would keep me from buying a CD25 again.
1. The outboard fits in a very small lazarette. It is very difficult to manhandle the motor in and out of there each time you sail. If I left the motor installed between sails, marine growth really got out of hand.
2. None of the bunks are really good for a 6' + person to sleep in. If you are only daysailing then this may not be a problem.