I was sponsored by L & M for many years before I went in a different direction. L & M makes a quality housing that WILL last quite a long time and should never wear out if you simply take even minimal care of it. Before that, I was sponsored by Gates whose mechanical housings are built like bricks but you still have to take care of them as well. A good electronic housings like L & M or Amphibico has greater convenience in terms of being user friendly than mechanical housings but it is really only a matter of getting used to either, knowing where the controls are by touch and a desire to film with the quality that either Gates, L & M or Amphibico offer. Yes, there are less expensive housings, but they really do not provide the quality of either of the companies I mentioned. Remember that aside from the housing itself, the quality of the glass port is all important and those Fathom Ports, while expensive as all heck, are the only ones that provide the optics you want for hi end filming.
As for the GoPRO...I have compared and reviewed many cams in this niche and all have their plusses and minuses. You can read any of the reviews on either the kenstone.net or lafcpug.org film and editing websites. I have reviewed the Contour HD, the Tachyon XC HD, the Oregon Scientific, both the first and second versions of the GoPRO HD and I forget just how many more but they will be there on the websites I listed. I am looking forward to reviewing the GoPRO HD HERO3 and should have my hands on it in a few weeks.