I hired a rather unusual version on the Norfolk Broads a few years ago. Instead of the usual centre plate or twin keels it had a fixed 3' deep keel. Sailed really well, a bit like a Wayfarer with a lid on! Can't say I would want to venture far but Ok in sheltered estuaries I'd say.
A bit cosy inside and would be very much more so with a centre board I would imagine. Most are amateur built and getting on in years so the ply will probably be delaminating on many of them. There is a good web site run by the Eventide Association.