I also was under the impression that amines were more chemical resistant than amides, or polyurethanes (amides for chems, amides for water barrier ,and polyurethane for UV protection).My understanding (which I will admit is limited) is that Amerlock 2 VOC is listed as a "High Solids" Epoxy and the Curing agent uses Amines (Not Amides) which give it a greater Chemical Resistance than an Amide Cured Epoxy.
Given, an Aliphatic Urethane (Like Amershield) is going to have a higher and broader range of Chemical resistance, but Amerlock was deemed suitable for the service environment. (Mostly due to wear.)
Now if Polyester Poly was compliant per SCQAMD, then it would have been a different story!
I believe amines are also used in chemical storage containments along with B-Phenols, as I remember. However, amines are extremely UV unstable unlike urethanes. Also, hydrocarbons are a different beast than say a chemical like Sodium hypochlorite. I'm leaning to the amide for oil protection, but I would get a coating expert's opinion.
I've had good success with Amerlock 400 (now Am 2) and amorshield polyurethane as an aesthetically pleasing top coat with UV protection.