I had an epoxy aggregate floor professionally installed and initially it looked fantastic - really rich looking and very durable. Within a couple of years it began to yellow and chalk. Five years later it's chalky throughout with a yellow band along the front of the garage doors where the sun hits it when the doors are open. Don't know if it was installed improperly but won't be using this type again.
In my manufacturing plant, I had the concrete floors polished to a 1000 finish. After polishing they apply a densifier which hardens the surface (but doesn't seal it). After eight years of rough treatment including lots of forklift traffic the floor still has a polished look. I'll use this on my next garage floor. A word of warning though, the concrete is not sealed and will stain if
oil gets on it so need to use drip pans. The rubber forklift tires have not marred the concrete so don't think car tires would either.