My (mostly RPG) group has always been exclusively GW has far as miniature gaming was concerned. When I reached my saturation threshold with their games, I just stopped playing with toy soldiers for lack of an alternative. Until fairly recently, when one of the movers and shakers of the group got fed with GW games too and started looking into, and promoting, other games.
His first extra-GW affair was Dystopian Wars but for various reasons (business model too similar to GW, unoriginal rules, lack of interest in the steampunk genre, lack of motivation to invest significant money, time and energy in a new range of miniatures and matching terrain, etc.) it remains a fairly confidential activity in the group.
More recently he came up with X-Wing... I was sceptical at first: although you don't need many, the miniatures are expensive. And I was cautious of anything coming from a major manufacturer and enjoying commercial success. Very snobbish of me, I guess: "if most people like it, I'm unlikely to appreciate it!" But he showed me the minis (which are very nice, a serious notch above what I was used to in pre-paint and a level I could live with having all my minis painted at), I read the rule online (I was certainly curious about the movement blind programming scheme, which introduce some fog of war and/or friction, two personal obsessions when it comes to wargaming) and ended up buying a box and playing a couple of games... And then I bought a second box... And two each of everything that's been produced so far! And that's not the best of it... I even got CINCHOME to give it a try! So far she likes it... She's got some days off coming, we'll see if I can hook her up for good!
A couple of ressources I've find interesting and/or useful...