Swing keel v. centerboards
The Catalina 22 is the most popular production sailboat ever made; however, I don't think the swing keel is the best answer for a trailerable boat. I prefer the stub keel/centerboard combination such as on the Oday 22, 23 and 25. With the swing keel, all of your ballast is in the swinging centerboard. It hangs on the boat with one pin. Catalina has made a zillion of these things and has come up with a pretty good unit, but its still requires a crank and needs periodic maintenance. Not for me. I like the stub keel, with the ballast encapsulated within the hull. The centerboard is unweighted and is directly controlled with a single line lead to the cockpit. Up and down with one hand, no cranks, pistons or mechanical device needed. Simpler, safer and easier to maintain. Granted, unlike Oday, Catalina is still in business and can support your older 22. However, all other things being equal, I would go with the Oday. That being said, if confronted with a choice between an Oday 22 or 23 and a Catalina 22, I would choose the boat that is in better shape. They are all great boats.What is the biggest boat with a centerboard? If you mean the biggest truly trailerable centerboard boat, I would say the Catalina 25 or the Oday 25. I think there are some water ballasted boats that might be a little bigger (Hunter?), but I hear that because they carry their ballast higher, they don't sail as well as the centerboard boats.