fnfan, interesting you bring this up because I have been looking at this reticle for some time and in all of my research I have not found anything that said at max magnification you "lost" the subtensions from 500 on up, this to me is a serious detriment to this reticle/scope. I knew the Leupold suffered optically above 15x (this coming from a previous owner) but now with this information it makes it even more distasteful to me.
I am now thinking that Leupold really made this reticle for the Mark 6 1-6x optic; however, that being said, I would be curious if you get the "full" reticle at 6x with that optic? If that is the case then clearly the 1-6x is the better choice of the two if you can live with 6x at the top end; however, with a reticle that's designed to go to 1200 meters, well, I just don't think 6x is going to cut it.
This is a serious design flaw from Leupold. When you get your scope can you verify this - that you lose the bottom holdovers beyond 7x?
The other issue I find with this reticle is that Leupold does not have any online ballistic calculator for it; the reticle is designed for the Sierra 175gr Matchking bullet at 2575 fps (which closely mimics the military M118LR); however, if your rifle doesn't shoot exactly to Leupold specs then now your holdovers are going to be off, and if you reload and get more than 2575, again, your holdovers are going to be off. So basically this reticle was designed for one purpose in mind, the military, and for that design goal it probably does extremely well, hence why the Navy chose it for its ECOS-O initiative.
I reload and I use different bullets at times so this helps to convince me that the CMR-W reticle is not for me. I do not like the TMR reticle because it only goes down to 5 mil from the center crosshair to the bottom, if they had done a design similar to the Nightforce MRL2.0 or the MSR type reticle this would have been so much better. This leaves either the H-58 or the Temor 2 reticle, the Tremor has it's known issues with it's mix of mil and ballistic holdovers and the H-58... well, that is an older design, why wouldn't Leupold have gone with the newest H-59 design and its enhancements?
For anyone interested in knowing what the holdovers are on the CMR-W 7.62 reticle in mils, check out this page -
http://blogs.militarytimes.com/gearscout/files/2012/05/CMR-W-7.62.jpg