This is the "Stealthy Photographer" group on flickr. Decide if you look cool or ridiculous on your own.
For myself, I bought the Lenscoat stuff when I got the 500mm and monstrous Gitzo 5 series tripod. It's cute, but it has to be some of the most cheesily constructed yet overpriced stuff I own. Honestly, those guys can't even cut a straight line on a lot of the pieces. Does it help me get closer to my subjects? Beats me. It does stop stuff from getting banged up, which isn't a bad thing. It will not protect your gear from rain, or dust, or sand in any meaningful way. You'll need a rain cover for that (Lenscoat actually makes a pretty good one).