I really wouldn't get too caught up in drives. I've heard some of the best drives made sound like crap in speakers. Verity makes the best crossovers in the world IMO to me that's more important then drivers. Plus they change the drives when they get them. I would be much more worried about cabinet and crossovers then drivers.
BTW I own the Sarastro's.
BTW I own the Sarastro's.