Hi G88,
Differences between Opti-Coat 2.0 and Opti-Guard
Opti Guard is a more concentrated professional version of Opti Coat 2.0. It takes more care to apply and cures faster. If applied correctly, it should provide a thicker coat. But will vary with application methods and amount used. If the same installer used both in the same manner, Opti Guard would be thicker. Professionals will prefer Opti-Guard because they can give the car back to the customer sooner without concerns about exposure to the elements and it will reach full hardness faster so its ready for real world exposure sooner.
Consumers will prefer Opti Coat 2.0 because it applies like Opti Seal which is very easy. You can easily cover an entire panel before it flashes, you have more time to spread it over the panel before you'd have a problem, and if you do have a high spot that dries you can fix it by hand with Optimum Finish instead of needing a machine and compound. Less experience an effort are needed.
As for the resin, the attributes and performance are the same with both: improved scratch, chemical, and environmental resistance/faster cleaning with less effort/dramatically less chance of etching from leaving contaminants on the surface. It may still stain, but won't permeate like normal clear coat will even with waxes/sealants applied.
The main difference is cure time and thickness per application. Opti Coat 2.0 can't be applied on glass surfaces and plastic surfaces as well.
Hope it help.