I've tried most of the aftermarket bridges at some point or other on my Fender/Squier basses - Badass, Gotoh, Schaller 3D, Hisphot, Babicz. To my knackered old ears none made any difference in the sustain or tone and certainly any miniscule effect they may have is going to be lost within the context of a band. But as DD says they look better and i found them more comfortable when resting my palm on them, which I do sometimes when playing with a pick or thumb. They are generally better engineered and some of them also allow for greater and easier adjustment of the strings. But, fundamentally, they do exactly the same job.