You are correct about the 31's
But I consider the Irwin to be a better Quality than the Hunter and O'Day of the 1980's and about the same as the Catalina. None were up to the Tartan. On the Ask All Sailors Forum there are a lot of Hunter owners who believe the newer Hunters are a great production boat and many think the same of the Catalina. I haven't heard anything about newer O'Days or even if they are still made. They O'Day) had a factory in Fall River MA where My old family home was, but I haven't been back there in many years.If I remember the figures correctly, The 1980 Irwin 37 was about $15000 more than the Hunter 37 and the Tartan was about $15000 more than the Irwin. I have owned two Irwins, a Competition 30 and a custom 37 Mk V. The 30 was exceptionally fast, an excellent Sailor and an excellent offshore boat. It had a bridge deck to minimize cockpit water volume, and was built like a tank. It had no openings in the cockpit, like lockers, to allow water entry below. But on the other hand it had minimum storage. I had to use the Stbd Quarter berth for storage. My 37 has lots of interior and is so much more comfortable below that it's hard to describe, but it is nowhere near the sailor that the 30 was. It is relatively short rigged but that means that I don't have to reef as soon as a taller rig would have to. But I was racing when I had the 30, and cruising with the 37. I have owned this one since 1994 and have upgraded it significantly. I had it in Mexico for 6 years and it behaved quite nicely going down the coast from WA.I wish that I knew more about the other boats.Why don't you go to the other site and get some opinions on the O'Day and Catalina. I know they will like the Hunter.Good SailingJoe S