Dunlop SportMax Road Smart 4's

[Grumpy Goat]

Just request the Roadsmart IV tire.  There is only 1 version.

Agreed.

As for other tires that have a GT version (e.g. Michelin Road x tires) the GT tire provides no advantage (and I have travelled fully loaded on both), in my experience, but being slightly heavier increases unsprung mass. They may cost more as well.