Re: Leupold and Ziess Question
I keep in mind how good the view is through the scope, and if the optical quality is relatively equal, I put the higher power scopes onto the rifle that will be shooting the farthest distance. My logic (for whatever that is worth) is that if I am shooting longer distance, I will need more power in the scope in order to determine things like target detail, what the target is doing, what details are around it and so on. The further out I shoot, the more optical power I need in order to view those details.
However, if the scopes are of significantly different quality (extreme would be Bushnell VS Hensoldt), the optical clarity of the Hensoldt at 16X would do me more good than the lesser quality optical clarity of a 20X Bushnell.
An added factor in your two scopes are the reticles. The TMR reticle will give you more detailed information (half mil) that you can use at longer ranges. In order to accurately figure the range using your reticle, you need to be able to accurately measure target size. Inaccurate assessment of whether the target is .4, .5, or .6 mils in size can make the difference between a correct elevation adjustment or an incorrect one. Having the half mil demarcation on the TMR reticle would be a nice addition to assist you in range estimation. Again, I would put the Leupold on the 338LM.
Both are nice scopes. You really won't screw up with either one, the above is just my preference. Other folks will probably like other features on the Zeiss and pick it. There are many reasons why I wouldn't disagree with choosing the Zeiss. It would be foolish of me to say anything negative about the Zeiss scope, therefore, it really can't be the "wrong" choice.
Upon further consideration, the Zeiss scope won't work out at all well for you. You should send it to me, and to console you over your poor choice in optics, I'll send you a nice box of steaks and some beer.