I use resin on the rear and semi-metallic on the front. I hate my disc brakes. Noisy and a constant PITA.

The resin brakes wear and brake fast and the semi metal ones squeal. I use the rear to feather speed in a group. The semi metal seems to be better for high speed and hills and the wear better. I don't get 1000 miles out of front resin pads. I use SRAM pads. Favorite? Swissstop Prince rim pads.