I really liked the Contour. Almost went with one. I hesitated because I really like the chest mount option for my motorcycle trips, and wasn't sure how the Countour works for that.
Anyway, I have an ancient 1st Gen Go Pro, and a bunch of mounts, including one for my AR. I finally gave in, decided to keep all my existing mounts and got a Hero 3 White just the other day. I really love the smart phone app interface! Much better than dicking around on that tiny LCD with gloves on, ya know?
And yeah...Both GoPro and probably Contour will be coming out with new models this fall. Of course! But honestly, the 3 White is already more than enough for my purposes, and it's not even top of the line spec wise.
Anyway, getting off track here. If you don't already have GoPro stuff and/or care about the ability to get more parts and stuff for GoPro, I would probably wait a bit longer and see if Contour is going to put out a new model. I did like the lower-profile size and appearance of it, and yeah, having a GoPro hanging off a rifle is cumbersome in some cases.