I have two boats: An RC-27 and an A Class Cat. The RC-27 is great for distance races, PHRF races, and day sailing with the family. It is a bit of a hassle to launch/retrieve short handed and is a major pain to breakdown and trailer.
I sail the A Class whenever I have no time to get crew or just want to sail by myself (although I have single handed the RC-27 many times). If I want to go to a normal cat regatta out of town, I take the A Class. If I want to sail with just my 2 1/2 year old daughter and it isn't too windy, I take the A Cat.
I would gues I sail the A Class 80% of the time and the RC-27 20%. I sail at least one a week all year round.