The resurgence of the Cat Ketch rig in the 70's was driven by Dr. Gerry Milgram's Cascade, a 37' or 38'
racing boat designed as an IOR
rule beater.
Gerry was a professor of Naval Architecture at MIT, and later did a lot of
work on America's Cup boats for Bill Koch.
Garry Hoyt, who later came up with the Alerion Express boats grabbed the cat ketch idea for cruising and ran with it. The early Freedoms were built by Tillotson
Pearson, who were also building the Aldens and J boats. Most of the hulls were balsa cored, but TPI did a very good job of it. A good
survey can allay any fears regarding a particular boat. The freestanding masts were retained by a urethane collar to keep them from falling out of the boat in a roll. One of the guys from TPI explained to me that they built the masts plenty strong enough to pull the boat horizontal with a
halyard from one mast. I was on one of the early 40's with a guy from TPI who just kept throwing the helm over downwind in about 25 knots, crash gybing repeatedly, to show that the masts wouldn't break. They really dolled one up with
teak decks and dark
paint for the actor Donald Sutherland, I can't remember if it was a 40' or 44'.
Everett
Pearson was a real evangelist for these boats for a while. He was really taken with the simplicity, and the fact that you didn't have a bunch of swages, turnbuckles, clevis pins, toggles, etc., failure of any one of which could drop the rig. I've got to admit, he had a point.
As I understand it, both Alden and Freedom were spun off into independent companies, although I had left RI by then.
A few Able 32's, Chuck Paine designs, were also built as cat ketches up in
Maine, but I think most of those have by now been converted to conventional sloops, which have held their value much better.
As other posters have stated, these are not wonderful upwind, but they fly on a reach and downwind, and are exceedingly easy to handle. The rigs were not just tossed together, TPI did some serious testing and engineering. I still see a few of the 40's and, especially, the 44's around. I think the 44 in particular is a pretty good boat, and the owners seem to like them.
I know Yves Tanton designed some cat ketches too, but I have no idea who built them, and I think they sell pretty cheaply.