It's good, though it will make your arm hurt. Make yourself a favor and mute the tab - you'll have hundreds of rotations per second, and the sound will play each and every single time. Even after these negative things, it's quite fun to try and optimize the speed. Through skillchecks, multipliers and the sort. There is an end, it took me 37~ minutes to reach it. Very clearly inspired by Crank, but you'd be hard pressed to find anything other than the actual crank and momentum bar that they share.