X-Ray Vision maybe
My Cat 22 has been berthed in salt water for 17 years, with no maintenance to the keel. The cable broke a long time ago so it is locked in the down position. I bought it a month ago and have been out in 15+ knot winds several times. Every now and then I hear the keel bang when a swell hits the bow at the right time. I'm not too worried about it, but I plan to have it worked on this winter. I don't think there's any way of inspecting it beforehand due to all the marine growth below. Top speed I've been able to achieve is 5.7 mph, according to my GPS.