My friend's dad owned a Bertram 31. Absolutely awesome boat. That and the 28 are still so well-regarded that you can buy a zombie hull, spend a shitload of money, and sell it without getting hit by the usual "dime on the dollar" return on pouring money into an old boat.
Speaking of modernizing...
They are great but the only reason there are S2's was because of the non-compete agreement signed when selling Slickcraft. It didn't cover sailboats. Mostly because nobody cared, since there wasn't much of a market compared to the powerboat market even then.
I still see old Slickcrafts out...
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CSY because they were made to be difficult for idiots to break. Last I saw, Com-Pac still has the 44 hull mold. I don't think anyone can afford to put as much fiberglass as CSY did though.
Also because they've held value, at least in nominal dollar terms, which is quite a...