what do you consider a go pro camera? How experienced are you with DSLRs? What is your budget?! for a semi professional sports camera I guess the Canon EOS 7D is still one of the best, if not the best. It´s very fast and has great focusing, and that´s what you are going to need most when shooting winter or motorsports. I´m not well enough informed about the nikon counterpart, but I guess the 7D is something to seriously consider. And now dont tell me you only got 500 bucks to spend.....

i want it on my helmet.
im not going to film someone else.

oh, so you actually mean a GOPRO camera

ok my bad.

yeah

I honestly don't have a clue about these cameras, but they look and seem so very very cool to have! I think there's ones that are even water proof etc. They are new to me, so I personally don't know a whole lot about them. I would love to buy one for zip lining this summer. But it seems a waste since I don't do anything like snowboarding/mountain biking/skiing/ or anything worth putting it on my head so I can see it afterwards. I wouldn't have much use for it other than this summer, but if I had nothing to do with my money, I'd definitely buy it just cause. What other things can you use them for?

Idk who knows about these.
But the best advice I can give you is look at footage from each one at night and day.
And to also look at the built quality and to have in mind what your going to do, if your going to snow board you should probably get a water proof one.

basically depends if you want HD or not
i would recommend you spend as much as you can on it and go HD as it will last you for many years and the usess are endless

i picked up the hero 1 camera is great i use it for snowboarding too there running at 200 right now to clear out or you pay 300+ for the hero 2