Hi Brian..I have a M23 that had a sticking center board. I removed the board and rebuilt it and all was well for a short time. When the board stuck the second time I removed it, sanded off some of the excess fairing from the first rebuild, barrier coated, painted (anti fouling) and reinstalled, all was well for a short time. When the board stuck the third time I could no longer deny what the real problem was, a swollen centerboard trunk. With boat on trailer I cut large holes in the side of the keel (thanks Sean for the pictures and narrative) I found steel of course (where is the lead that was advertised?). About 60 % of the steel was encapsulated in resin and was fine, the rest which was in the center area of the trunk was loose and had settled like beans in a bean bag causing great pressure on both the trunk and outer wall of the keel. I decided to re-install the loose steel (lead is $2 a pound) and poured it in layers of resin just like Sean did with his lead. All is well and since there was no sign of water intrusion I think it should be a long lasting fix. Soooo I would say that the center board is a potential problem on any M23, if you love working on boats it is a perfect choice. That said I LOVE my boat...John Muller