Depends what grip you have at the moment. Leather grips differ in width, I think the Prince leather is 1.4mm whereas most synth grips are around 1.6 to 1.8mm. I put on a Wilson leather grip that was about 1.8mm, it hasnt increased the grip but has improved feel.
"Tennis is just chess with balls."
Sometimes: Dunlop Biomimetic 300 - Sometimes: Prince Exo3 Graphite 93