For the right person, they are a great boat but they are not for everyone. What version of the 25 are you looking at? The designs are dated so they have a little bit less room, less speed, and heel more than some modern boats. That said, they are extremely able boats and a real pleasure to sail.
If you like to race around and be the fastest boat in the bay, then they are obviously not the boat for you. However, if you value good looks, good build quality and the feeling of this type of boat, then it would be an excellent choice. I happen to fall into the latter category and the 30 that I have is a wonderful boat for me. It is quicker than I had originally expected and has a wonderful feeling to sailing.
There is a really good cape dory owners association that might be worth checking out.