Depends on your intended use really. I gave up on the cheap ones and picked up a good Fluke 177 from a sparky who had been given a new one at his new job so sold me his old one. Came with an amp clamp as well which is really useful. The advantage is that they can be calibrated properly.

Fluke set the standard in DMM's. They are reliable, accurate, robust, can be calibrated. They have a range of accessories also and have a much higher electrical safety rating which makes them very safe to use . On top of that they are difficult to blow up and with all those features of course they are very expensive. They quite probably make one with a high IP rating too, which will make it even more costly. To Krow's point, most multimeters would struggle when exposed to a salt water environment. You would want to be pretty careful about keeping it dry, especially once it is in storage. A zip lock bag inside a too box maybe.