Playable Game Slices are now online.
BetaDwarf has released playable game slices, in effort to gain feedback from the community, and reward the community for supporting.
You can as individual try out the weapons in game, and even play out a little challenge with a buddy of yours. (2-player challenge require connected ps3 or xbox360 controller.)
There are guides to help you setup your controllers for PC. Mac does not require a setup as it just works plug-and-play.
(Requires Unity Webplayer plugin)