I have owned a Formosa 51 for the last 10 years, three trips from San Deigo to Puerto Vallarta and a bunch of local stuff on each end. You are right that they are not easy for one person to handle, primarily when docking. But I have found that the space and comfort when cruising is fantastic. On both the Baja Ha Ha runs I did we were one of the first 20 boats to finish each leg. We did motor more than some, but with 500 gallons of diesel we could. On the bash north in the spring we stayed warm and dry the whole trip. Winds were 15 - 25 on the nose with 10 -18 ft seas. All the light weight modern boats turned back to Turtle Bay and we just jogged along into it. Only had green water on deck twice, we kept it at 4 - 5 knots and just kept going. Would not trade it for a newer boat.
They also have a lot of character, not just looks but crazy electrical, bad decks, and strange plumbing. Once you either fix those things or live with them they are a pleasure to travel in.
For more info checkout the Formosa Owners site
Force 50 and Formosa 51 Owners Group