If at any time you wish to change from a phenolic tip to a leather tip, it is easy to simply machine off the phenolic "tip" section of the piece and make it a flat-faced phenolic ferrule that accepts any regular leather tip.
When the cue ball is hitting the rack, it is seeing an up to 15x weight implied difference. Hard to explain but when the cue ball hits the rack, the forces there should be 5x greater than when the cue stick hits the cue ball. Nope, it's the break shaft/tip. Hard phenolic tips will do, G10 even more so.
sZey.