I'm exclusively in the Sebago Clovehitch II camp. These shoes come in wide and extra wide widths, to accommodate my developing bunion. (Thanks, Mom, I really appreciate that genetic hand-me-down…) Every other boat shoe I have ever tried on is FAR too tight in the toe box. I've seen some big guys (who should have wide feet) wearing regular boat shoes, and I don't know how they do it. (For the record, I've been a ski boot salesman, so I probably have a weird sense of foot shapes and sizes…)
My current pair is the Dark Taupe/Dark Brown combo, which is softer and more comfortable than the last pair, which was the Walnut, made with stiffer leather.
http://www.sebago.com/US/en-US/Product.mvc.aspx/11608M/20261/Mens/Clovehitch-II?dimensions=0
I know other people who love the Crocs Ace Boating shoe, but they don't make them anymore. They look like original Crocs, but with a Velcro adjustable back strap, and a different sole material molded into S shaped channels. They aren't razor cut siping like on Sperrys or Sebagos, but they do kinda stick to wet decks, I guess. Original Crocs soles are HORRIBLE on wet surfaces, but these are ok. I was lucky to get one of the last pairs on Amazon.com last spring, and they are quick and easy to get on and off. But they don't fit too snugly around the foot, so I feel like I don't have the greatest stability if my foot is slipping around inside the shoe, whereas I can cinch down the lacing on the Sebagos if I need to.
There is actually a Crocs store at our local outlet mall. Last spring, I went in looking for the Ace Boating Shoe, not realizing they had been discontinued. Everything they had that was a "boating" shoe may have had Docksider-type styling cues, but the soles were completely unsuitable for wet deck traction. I don't know if they have changed anything for this year. I guess it's too bad they don't make that Ace Boating Shoe anymore, it was pretty reasonable.
Brian