The dirty secret is that Go Pros are quite useless unless you consider the post side investment as well - you may as well be using a $100 knock off.
720p is more than hi res enough if you are going to web
The xtra frame rates (anything above 25p) are awesome but are a waste of time if you dont have the correct editing software to reconform your 120 fps to play back at 25p - which gives you 5 x slo mo - (1 sec recorded lasts 5 secs on screen)
Imovie and windows movie maker just throw out the extra frames and use 25 p - so you generally wont get to use the frames created to make that beautiful slo mo.
Hence all the crappy slo mo you see on the web with the stuttering frames where people thought they were using the higher frame rates but the free software just ignores the extra frames.
You need final cut x , final cut studio, Premiere Pro etc etc to take advantage - if you dont have these then just shoot at 720 25 p and be done with it. - these more professional packages give you the benefit of being able to work with transcode mastering formats like Pro res
There MAY be a Cineform / Mpeg streamclip workflow to capture and render out reconformed movies - but these workflows often depend on you having the intermediate codecs - which having Final Cut / Premiere gives you.
If all this sounds complex - (it is) - and its the full story that most people dont get when buying a video camera.
Final Cut X is excellent value at around $300 dollars online if you are apple esque.
I had some of the first go pro 2s in Australia (i ordered 4 of them) and have found that over the years i just tend to use them as locked off tripod wide angle timelapse options these days - MOST (but not all) mount shots are a waste of time - - like the nose mount (unless its a SUP where you can get the camera away from the riders feet)or helmet cam (unless you are tracking someone ELSE)
Treat them like a normal video camera and there are tons of options to have fun - i did a trip to Japan where i ONLY used a go pro (amatuer snow boarding action alert)
If you have a steady hand Go Pros are great for hand held dollies / handheld steady cam work as the wide angle tends to iron out the bumps.