There's a guy who has a site where he compares different mirrorless for BIF. He rates the R5 highly, but he is using settings I would never use. He uses Case 3, which is the anti-tracking mode and designed to instantly focus on new things. I use settings that are usually recommended, Case 2 with tracking slider to the left and acceleration/deceleration to the right. I find the acquisition really fast and then it sticks like glue.