My friend is hitting a Prince More Thunder OS. It had a fresh string job - Klipper kevlar 16 mains/Prince SGD16 crosses (60/64 constant pull). In the second set (singles) the kevlar mains were notching! I don't think it will last a second match. My friend is tough on strings - poly won't last due to shearing from framed hits. Any thoughts? Should kevlar notch that quickly? We used the KlipperUSA Kevlar as you can get it in full sets and pick your own cross. We thought kevlar was tough on the arm, not the wallet! Any suggestions?