Re: Vortex PST vs Mk 4
I also carried and used Leupold's in the Army over just short of 10 years, mainly the M3A. I saw and heard stories of that scope take unbelievable abuse (fell out of M1950 WPNS case into drop zone, run over by Bradleys, fell out of Blackhawk, etc.) but we never really did anything like a tracking or box test to see if the gears had shifted.
Zeroes would be confirmed, and adjusted as needed, then run the guns out through the targets on a KD or transition range out to 900m, with the double-wide E-type at 900 so you could actually get a hit with M118 at that range in modest wind.
Anyway, I bought a LR/T 3.5-10x40 for my first AR10, thinking that was the best glass to go with at the time, which was pretty high-end then. I eventually sold it, but it was a decent scope.
I've since purchased or used the S&B, USO, NF, and Hensoldt a lot, but have settled on the Viper PST's as my go-to tubes now. If I'm going to spring money, I want it to go towards a clearly superior glass, so I'm holding out for the new Hensoldt.
I do spend a lot of time behind the 2.5-10x44 PST, and I jumped over to a guy's Mk IV 6.5-20 at the range. Bang! The clarity of that glass was unmistakably better than the 2.5-10x44 PST, but then I asked the guy if I could feel the Mk IV turrets...
Mushy and questionable as to click position, which is why I don't buy the Leupold's anymore. Even the new $4000 uber Lupy's have mushy turrets, and I checked specifically for this at SHOT this year, thinking they might have stepped up to the competition in that regard...nope.
I will agree with the poster who mentioned the Nikon Monarch glass quality being very close to my Viper PST 2.5-10, although my PST has a <span style="font-style: italic">very</span> slight edge over a 2.5-10 Nikon I compared it to.
I have no problem resolving an 8" Shoot n' C at 1000yds in mirage enough to shoot sub-MOA with my 2.5-10x44 PST on top of the GAP .260 Rem AR in late afternoon lighting in the summer in Utah, but it will not help you in a "know your scope (budget)" stage at a practical long-range match.
The 6-24x50 PST's I have looked through had a clearer FOV and image quality, which I think has something to do with the x50 OBJ lens, in addition to whatever glass they're using.