From the horse's mouth:
Source: A MiG-29 Pilot’s Inside Account Of The Changing Air War Over Ukraine
R-37M is forcing Ukrainian pilot to fly low and dive in order to avoid it. You can't gain air superiority if enemy forces you defensive. So in that regard Su-35S combo with R-37M is doing a perfect job. Plus, as I said R-77M is now under serial production. It has 200kms range, dual-pulse solid rocket motor and AESA seeker. Once US/NATO decide to send those F-16s/F-18s to Ukraine, Russians would use R-77M to destroy these US fighters.

Russia’s Best Missile Can Hit Ukrainian Jets From 80 Miles Away. But Ukrainian Pilots Know How To Dodge.
“We created different tactics for how to avoid this missile—and that’s why it’s not so succesful against our jets,” Ukrainian Mikoyan MiG-29 pilot “Juice” told Lithuanian broadcaster Delfi.
