ZEISS definately over Leupold.
I know of two Leupolds that have been trashed by ultra-mags. They just do not hold up like they used to. I have shot a couple of the conquests and they are clear, clear and they have held up on the mags. My old hunting buddies used to shoot nothing but Leupold, now there is not a single leupold on a mag rifle because of the problems they have had. I have a Kahles and Redfield on my mags, my other buddies have one Zeiss and 6 burris on theirs. On the four ultra-mags are all burris execpt my one with the Kahles. Don't get me wrong Leupold fixed and sent back the scopes but they sold them.