I have to agree with
about the bullet designs. The Gold dot's have nice reviews as well.
The biggest thing is bullet weight retention and even mushrooming, staying uniform due to the design of the bullet.
Older hallow points tended to fragment more and have non uniform shapes. That can lead to tumbling and trajectory changes as the bullet passes through tissue as well as loss of weight end energy.
The ideal hallow point retains weight, holds a uniform mushroom shape, keeps a decent trajectory through soft tissue and insuring the energy doesn't bleed off or disperse due to fragmentation.