Look up HD cameras on the RC sites. There's a ton of them recording at 1080/60 for anywhere from $50 to $100. That's why GoPro is going to have problems with trying to sell a $100 camera for $500.

I have a JVC Addixion 2. I got it from work through the catalog for 20 year anniversary. I haven't used it on the bike yet but I use it all the time on the kayak because I didn't have to go out and spend another $100 on a waterproof case. At $300, it is waterproof and shockproof. I don't know about the shockproof, but I've used it in the pool under water with the kids and in the water with the kayak.

The proprietary mounting system with GoPro is another big downfall. My JVC along with any other camera on the market takes a simple 1/4-20 thread to mount to anything. This means DIY as well as thousands of cheap universal camera mounts. I can get a $4 handlebar 1/4-20 mount that works perfectly rather than a $20 GoPro handlebar mount.