I tried a while ago when I was going through my Steam library and looking at all the games I haven't played yet (there's a lot). I thought I'd give Gatling Gears a crack but I get the error message "Failed to start game (missing executable)". My friend also gets the same message, so I wonder if nobody can play this game anymore.
I've tried all the necessary steps to fix this to no avail. I also notice that you can't seem to buy this game anymore neither on Steam or Origin so I wonder if that has something to do with it. There is a small thread on the Steam forums with a few people with the same problem but no solution.