Are certain grades better than others?

No grade is actually better than another. They have different appeals and applications:

Canada #1 Extra Light, Canada #1 Light, US Grade A Light Amber and US Grade A Medium Amber:
These grades offer a very delicate, subtle flavor.

Canada #1 Medium, US Grade A Dark Amber:
These grades offer the optimal taste balance: a good, pleasant, and full-bodied maple flavour. These are the most widely appreciated grades of pure maple syrup in supermarkets.

Canada #2 Amber, Canada Commercial, Canada #3 Dark, and US Grade B:
These grades have a stronger maple taste, and are best for cooking or industrial use.