I have a newer 1981 Contest 31 HT. Sails well, lots of room down below, solid as a rock. Recently stripped the bottom paint off and found hundreds of gel coat blisters; only a small blister into the fiberglass. I will be working on that this month.
My friend has a 1970 Contest 30 with Atomic 4. His only problem was a cosmetic crazing of the deck. We both have small fresh water leaks. He put in 2 new bladders; I will put mine in this fall.