Most people ask which one is better. On a commercial job that is the wrong question, because the good systems use both.
Epoxy is the workhorse underneath. It bonds hard to prepared concrete and it builds body, which is what gives the floor something to absorb impact and abrasion with. Polyaspartic is the finish. It cures fast, it holds color under UV instead of ambering, and it shrugs off the scuffing that shows up first in a busy aisle.
Our commercial build is an epoxy base coat, decorative flake and two coats of polyaspartic. You get the thickness from one and the return to service speed from the other.
That last part is why facilities care. A straight epoxy system can hold a space out of use longer than the operation can afford.
Working out which build fits your operation? See how we spec epoxy and polyaspartic systems for St. Louis commercial floors.