Interesting string. I don't know how one has this conversation without a price comparison. While cost may not be an issue for the buyer, value should be. I looked at Midway -- yes I know there are other vendors but it's useful for a quick comp -- NF comp, $2,400, Trijicon MRAD $1,899 (MOA, special order $1,750) The Delta Stryker mentioned in this string as a Trijicon fellow is $1,590.
I own two Stryker HD 5-50s, one the older model, one current. They are mounted on my Savage F/TR rifles. Apart from the size of the numbers on the turrets I can't tell any difference between them. I use the Delta parallax wheel on both and get incredibly clear images. I am on record as saying I think the Delta scopes punch $1K above their weight and I still believe that to be true. I like the Delta reticle better than the Trijicon, but hey, chacun a son goute.
The NF comp has a 30mm tube, correct? The Trijicon or Delta 34mm. I am retiring all my 30mm tube scopes. 34mm and up from now on for me.
Speaking of which... how good is the Delta? I have really only one comparison, to my Valdada G2 Recon, also a LOW product except it has some German glass. It is a superior scope but then it's $3,000 and has a 40mm tube. Other than that, honestly, to my old (renewed) eyes, it's a pretty close thing.
Folk have mentioned warranties. To bastardize that great American, Forest Gump, warranties are like a box of chocolates. I now own a nice Nikon camera that I have in place of my lovely Nikon 'scope whose reticle went upside down and Nikon decided they weren't in the 'scope business any more. The best warranty I've seen is from Blackhound, whose scopes sell in the low hundreds, not thousands. They had a replacement scope on its way to me before I'd even printed off the free return label they sent me. So long as your manufacturer has been in business a while, I think you can reasonably expect fair treatment (I hope).
In closing, I think if your price point is over, say, $1,500 and it's a LOW product, you're probably not going to be disappointed.