I've had a UWS aluminum box for about two and a half years now, and I have had zero problems with it. It still closes well and has remained watertight. I apply a little white grease to the latch pins when I think about it, and other than cleaning it out periodically, I've done nothing else to it. Like one other poster said, the key wants to be stubborn sometimes, but a little jiggle takes care of that.
Unless you're set on black, like I was at first, think about the temperatures where you live. I was talked out of a black one by the fact that the aluminum will keep the contents a little cooler in summer. I carry WD-40 and various other pressurized cans in there, and I didn't feel like creating IEDs out of them in the heat of summer when I didn't have to...

Anyway, mine cost about $270 or so, but I had it delivered by a friend. I have been very pleased as I have seen some around that don't hold up nearly as well.
Good luck with your shopping!