Re: Leupold Mark AR
I had a Mark AR 3-9x40 on top of my AR15 and for the price, the glass was definitely hard to beat. I sold it because I didn't like the turrets being 1/2 moa rather than 1/4, the turrets weren't exposed, the "calibrated" drop numbers on the turret were waaaaay off for my 16" AR, and it had a duplex reticle (I like fancy reticles). The "BDC" knob still had standard markings, it's just that I can't imagine a 16" AR15 pushing 55gr ammo at 3100fps. That being said, it did serve me well for a year and a half before I sold it for....
A PST 2.5-10x44 which I currently have on top of my AR. The PST glass is very similar to the Mark AR. I got it primarily for the reticle, warranty (Vortex treated me right when I had an issue with another scope), increased travel (86 MOA vs 56 MOA), and illumination. To my eye it seems that I am having issues with the parallax at my 100yd range, but I have shot better groups with this scope than the Leupold.
All in all the Leupold Mark AR was a very nice scope especially for the price and I was pleased with it. However the lack of reticle diversity, illumination, and limited travel (the 4-12 has 55 MOA) ultimately had me looking elsewhere.