SimonTheBeetle: And also... I never timed it or anything so I cannot confirm, but the mobile swing meter feels noticeably faster than the PC one. (Nevertheless, playing on PC doesn't do any good to me because the swing meter on my PC browser jerks so much that it is virtually a carcinogen. So I gave it up for my health after few trials earlier this year.)
I gave up playing a few years ago when after upgrading windows my meter, which had been lovely and smooth, went bananas.
Since I came back I've found it to be much more steady but I recently downloaded a lot of different browsers and gave them all a go. Comodo Dragon won, it's as steady as my old setup was.
It may not be the one for you but trying a few out just might sort your PC game.