See if you can look through one. At 6x, both my girlfriend and I really disliked shooting the Swarovski 1-6x24, since the exit pupil became so small. The Zeiss addresses that, with some tradeoffs.
The Vortex has a better reticle for hold over, which is nice. That's the one thing, other than changing the on/off controls, that I'd change on the Zeiss.