Compensators work very well at reducing recoil on semi-automatic pistols or any pistol for that matter. If you want to increase your accuracy with a Glock then a custom barrel and comp can do wonders. Recoil can rob accuracy from you. The more you decrease recoil the easier it is to shoot accurately.
Watch this video of a Glock 21 with a 6″ Lone Wolf compensated barrel. Recoil is very low.