I can highly recommend the Kirk BH-1. I've had it for several years now (4-5 years I think?), it's seen everything from snow, to deserts, to swamps, to salt ocean beaches. It hasn't given even a hint of a complaint, and I've never cleaned it anymore than simply wiping off any visible dirt that I see on it.

Mind you, it's never actually been submerged in water so I don't know how it would handle that, but it's definitely seen a good bit of sweat from my hands and humidity from the air/mist.
I mostly use it on my digital (1-series with medium sized lenses, longest being a 400/5.6) but I've also used it a good number of times on my 4x5 folding camera (when I have to choose to bring only one head between my digital and 4x5 together), and even once on my 8x10 folding camera. It held the 8x10, but it was very awkward to use (which I had guessed before I tried it) but I more or less was just trying it out to see how unwieldy it would be.
I believe the BH-1 was right about at $350. If you don't plan on using any big telephoto lenses, then you could probably easily get the smaller BH-3, which I think is about $100 cheaper or so. If it's anything like the BH-1, it should be quite reliable.
I've heard good things about the RRS and the Markins ball heads too, I imagine realistically any one of the big name ball heads you choose would probably serve you well. If you can handle some of them yourself, that might be good, as they may have a different feel to the knobs. Keep in mind, that you don't really need to crank down on the knobs to hold the ball steady, I had a tenancy to want to do this at first, but it's not really needed. Just snug it up and it'll hold fine
I dont know if RRS or Markins have plates that are molded to your camera or not, but the Kirk plate that I have is molded to the shape of my 1-series, and it's really pretty sweet, never have to worry about if the plate is going to rotate on you or not. Literally, I think it's been on the camera for several years now and I've never once even tightened it after I initially put it on. Since it's molded to the shape of the camera, there is no way it can slip and rotate

I would highly recommend this as well, it's a very nice piece. If RRS or Markins don't have something like that, I believe they both use the same "Arca" style release plates like Kirk does, so you could use the Kirk molded plate on either one of them. I could be wrong though, double check that before you order one!
As far as the quick release mechanism itself, personally I like the type that requires you to screw the clamp down, rather than a lever or a switch. A lever or switch I think could possibly catch on something and accidentally pop open, where a screwed down clamp would not have that possibility. Yes the screw is a little bit slower than the lever/switch, but I like the piece of mind
