Rating: 5 / 5
I started really getting into cold weather and water proof lightweight gear when I was saiing a lot. There it is truly a matter of survival.
If you want any and every kind of waterproof gear you can think of, start there. Same for line. And compass and GIS systems. (I have been thinking of asking them to design a safety beacon strobe light, flashlight, whistle, mirror, watch, compass, sewing kit, dry match holder, screw driver for eyeglass, etc. tool under 2 oz. ... but then I'm guessing you all can do that same thing and even better for backpackers.)
My favoite store location is Sausalito, CA ... but they have them all over now and they are online too:
They have great sales on stuff.
Sailors test their gear in life threatening situations all the time so I have great faith in their products and recommendations. (... brings to mind my idea of a hiking sail which can get me down the trail on UL roller blades in a good tail wind ... but that's another story ...)
So they get a real Big 5 for the variety and quality of their gear -- although you really gotta check out the gear for quality since a lot of it is mass produced, they have a great return policy and service to go with it.