Rifle Scopes Leupold Mk4 8.5-25x50mm ER/T M1 FFP MtTMR or Bushnell G2DMR 34mm which one to get.

It's worth the extra money.... I suggest you look through both pieces of glass first-hand before you purchase though....that way you'll only cry once. ;)

I have a Leupy M4 4.5-14x50 TMR and I like it a lot - though my newest scope is a Vortex PST FFP for long range work.
 
Get the bushnell, the leupold is nice but with a low end of 8.5x you're kind of limited at shorter ranges. I had the leupold before, it's a nice scope but I'd go with the bushnell given the choice.
 
I also had the exact Leupold you're asking about, while it was a decent scope the 8.5X low power is not very practical. I upgraded to a 5-25X Steiner and I'm glad I did. I can not comment on the Bushnell but I would give it a try as a lot of guys on here run them. One more thing about the Leupold it has a lot of tunneling on low power.
 
I've owned similar Leupolds (a 6.5-20x FFP and a 8.5-25x SFP, both with M1 knobs and TMR reticle), and I currently own the Bushnell DMR with the G2DMR reticle. Optically, they are similar to my eyes, but I personally feel that the Bushnell is flat-out a better scope due to its increased zoom range (which gives it a far more usable lower magnification limit), greater range of internal adjustment, and a better reticle. Seeing as how the Bushnell is cheaper, I really think this is a no-brainer.
 
I run an ER/T on my 7mm and have been very happy with it. I have not used that specific Bushnell in your comparison but I highly doubt you would be disappointed in the Leupold.