I bought one in December last year (also a 31b) and and am currently carrying out quite an extensive refit.
The boat builder working on mine reckons they are great boats and from what he has seen of it so far (which is most nook and crannies) thinks they are strong and fast.
Watch out for the forestay fitting though. I was having the toe rail replaced and a piece of aluminum dropped out from under the forestay. I've now replaced it with a 5mm stainless steel shoe. Had I not been replacing the toe rail it wouldn't have come to light.
I've done quite a bit of research on these boats so if Ican offer any help please drop me a PM and I'll send my tele number.