The magic of the turret is that it's a single stage just as easily as it is an auto indexing turret. In a couple seconds it can be changed back and forth between single stage, auto-indexing and one cartridge to another. I can go from producing 200 10mm rounds an hour to single stage, 1/2 MOA accurate .204 ammo in LITERALLY 5 seconds.
I see no advantage to a single stage. There is only the theory, for which I have never seen any evidence, that more accurate ammo can be produced on a single stage than a turret. Even if this were true (and I see no reason to believe it is) it would certainly have no meaning to a handgun shooter.
If you want to start single stage, which is probably good advice for many people, take the indexing rod out. When you want to go faster, put it back in. It's that simple. The fact that the Classic turret is "auto-indexing" is certainly no reason to buy a single stage instead.
The Classic turret does everything a single stage can do, and much more, and a single stage does nothing a Classic turret can not do.