I use nVidia Shadowplay to record 1080p/60 @ 50Mbps.
Considering my PC spec is quite low spec/old, I don't get as many dropped frames as I would have expected.
The couple of vids I've uploaded are here...
https://www.youtube.com/channel/UCQ0lcL2NcZ4u-5H8OO2UnvQ
Videos look pretty good, but I only see 720p. Not sure if that's the HTML5 player's fault or if you only uploaded 720p.
What CPU are you using Morbad?
i7-5820k @ 4.2GHz
Not sure my 3570 can handle 60fps constantly.
Probably not at the same settings, but 1080p with a lower quality CPU preset should be doable for 60fps.