Agu

It's about nothing else than what downsides you wanna deal with and work on improving. Lack of speed vs. Lack of precision, flicking vs. tracking vs. crosshair placement & click-timing. Practical difference between 8 and 8.5 on the other hand is literally nothing. You should be comparing something like 400 / 4 vs. 400 / 8.5 vs. 400 / 20.

There's no point trying to calculate it. Just try to match your hand movements in Osu! to what you usually do in OW, and set your sensitivity based on that. Trying to match Osu! sens to OW sens on paper is like assuming that aiming in OW would be about making 180 degree flicks on Reinhardt-sized targets, which it isn't.

The guy is literally using his mousepad a starting point. He could buy a new mousepad of a different size every day, and the value would also change. Has absolutely nothing to do with any kind of "inner perfect sensitivity". At the part where he said how very low sensitivity is exhausting, I was assuming the lowest lows, 70cm+ range to begin with. It just takes away credibility from him, since it's obvious he just tried it once somewhere, sometime, rather than relying on any kind of objective information such as that there are several pros using those sensitivities.

It's bs because between 10cm/360 and 86cm/360, literally every possible sensitivity is being used for every aim-based hero in the Overwatch pro scene. The only exception is that there's nobody using slower than 72cm/360 for DPS (the lowest is Birdring (Widow/Tracer/flex) with 71-point-something for a 360. Also, there's so much misinformation in the video. He says how very low sensitivity is "exhausting", while truth is that it becomes completely effortless after your arm gets trained to it. Having a 50x50cm+ space for mouse movement is a bigger problem.

I used to play OW with 400 / 4.33, and felt that 400 / 1x requires similar mouse movements in Osu. Currently I'm practicing high sens 800 / 12.37, and 800 / 2.5x in Osu. Honestly, just think Osu screen as "your typical solo 1v1" in OW, and try to match the sensitivity for that. I'm not a pro in either game tho, 3.1k as Widow/S76 & 540pp in Osu.