Leaderboard

MMV0% is the best possible method since it scales on the focal length. However as you mentioned the issue comes into play for low sensitivity players since the scopes get too slow. What i would recommend is obviously raising the visual sensitivity, aka your overall sensitivity or your starting games sensitivity. Also just note that you can still have incredibly good tracking since tracking is close to the crosshair, what they say when they mean by it's bad for large flicks, they're talking about flicks at the very edge of the field of view (or monitor however you choose to define it) or outside of your field of view. However you can obviously improve over time and have better overall aim thanks to the fact that you're matching your sensitivity almost perfectly through every aim type on every game on every scoped weapon. TLDR: raise your sensitivity on your main game and use mmv0%

There is no right or wrong answer to this, as it comes down to personal preference. If you do 100%, this means that moving 50% of the monitor distance will be slightly different between different FOV's. If you instead do 50%, moving 100% will be slightly different, and so on. Some might find it better to match 100% with hipfire, and go down as the zoom levels get higher. Say 50% on a 4x scope and 0% on snipers scopes. Higher zoom levels also means more tracking and pixelhunting in many cases, so 0% might make more sense on snipers etc.