I think you gentlemen should read the quote from Mr. McMillan of McMillan stock and Sniper Rifle fame. He says it pretty well for the Shepherd. As for me, I have two presently mounted on rifles. One on a 30-06 Ruger M77MkII and another on a Remington 700 CDL in 35 Whelen. I've killed deer in Kansas with both rifles from 30yds out to 500+yds using just the circles. No issues with zeroing(you do have to follow Shepherd's directions, tho) but the mounts have to be right and so do the rings. On the Ruger I had no trouble, but I had to use Millet Adjustable rings on the Whelen. I also have a Shootist (circa 1985) from Shepherd that I bought in Hawaii. It got pretty stiff after around 28 or 29 years, so I sent it back and they rebuilt it for the shipping and handling price. I still use it, and it and one or another rifle have accounted for around 25 or 30 deer here. Last fall, I shot the Whelen with 225 gr. Sierras on Ft. Riley's 1000yd pof range and hit the 700meter pop-up targets in a 20mph wind using the circles and ballistic table. I adjusted into the wind on a 400yd steel plate and adjusted again for the 700m targets. After hitting them, I dialed back to a zero windage zero without having to refer to notes by just lining up the two reticles. Try that with any other scope. And I used it last January during Doe season to kill three doe at three different ranges on the same bean field in about 30-40 seconds. Try that with any other scope. I just bought No. 4 for my 300WinMag. And yes, you can beat the optics if you buy a 1500 or 2000 dollar scope, but not with a comporably priced scope.