Jenn, if you go over to paddler.net or paddling.net (I always get it wrong), they have a lot of reviews of sit on tops.... Definitely they do make some serious boats that are sit on tops, and if you're in the surf zone or something like that, sometimes it's an advantage to have a boat that won't fill with water and it's easy to get back into if you're pitched out.

You can definitely do what you want to do in a sit on top kayak... as for how good they are, that's sort of a question of how fast do you want to go and what sit on top you're going to get... sorta the same debate you get between a rec boat and a sea kayak when you're looking for an enclosed kayak... Sit on tops can be a much wetter ride, but unlike rec boats without bulkheads, they don't need airbags for additional floatation, so you don't have to worry about the boat potentially sinking if you get flipped in the middle of a lake or open water.