As with any hard break tip, It will only be as good as the stroke behind it. A good solid, smooth stroke will give a good break. Being as hard as the cue ball means less force will be needed to break the rack, as the tip will not absorb any of the energy, it will transfer it almost 1:1 to the cue ball, depending on the ferrule material and the solidness of the shaft. As far as chipping a cue ball....have seen that happen with a leather tip on a break using a cue ball that was beaten from hitting a concrete floor, but have not seen it with a good condition cue ball, using either a phenolic or G10 tip. I have seen chipped cue balls, but usually these are ones that have seen more action then most of our Veterans have. I personally feel that happens more due to cheap cue balls being purchased by the pool halls to save a buck. I recently had a cue ball at a respected hall locally....during a tourney, seemed weird with rolls....when rolled by hand, it went almost sideways......
A phenolic tip and white diamond, and G10 all rate in the same range of hardness....it's not like g10 is made from such a different material that causes cue balls to explode on contact. It is only a fiberglass resin....phenolic can be harder, depending on the grade, the only difference is the fiberglass will grip the ball more, which will scratch the surface....but not crack it
Dave