I'm running a NF 1-4 with IHR reticle in a LaRue extended QD mount. I forget the model, same thing as the LT-104 except the cantilever extends farther forward. Railed gas block because it looks good, although I've run a standard front sight tower with flat top upper before and really didn't see enough of the front sight tower in the scope to be a distraction. And still using a standard A2 butt stock because it works for me, although when things calm down this winter I'm gonna try the Magpul UBR.
A neighbor is buying one of the NF 4.5 SR scopes, essentially because he can, although at the moment he is still running the same scope as me and shot remarkably well during NRA week at Perry this year. He had an epiphany during CMP week, while still trying some things out, and finally figgered out what he needed to do to make things click for him. I would in fact love to buy one of the NF 4.5 scopes but have decided to continue to run my 1-4 for at least another couple years to see what else comes along as scopes evolve.
Having said that, I had a nice chat with Dennis DeMille and he's running the 1-4 Vortex with 1/2 minute click and you ignore DeMille's advice at your peril.
The advantage of the scope to me is the improved sight picture. The disadvantage to me, is the improved sight picture. Every little herk 'n jerk is easily seen, especially in Standing. I have had to relearn to "accept your wobble zone" again.
Also, there is another thread on US Rifle Teams where the NF rep and some other people recommend using a rear scope cap with a small hole drilled or punched in the exact center of the cap. This to ensure your eye is centered on the scope tube. I've had significant issues with this with iron sights when I get tired and loose my attention, and feel that this helps me with the scope.
I have a very firm opinion that, contrary to what I've seen some other folks seem to think, it is essential to get your eyeball centered on the scope tube or shots will spin off call, and that the scope cap with the hole has helped me with this. Your mileage may vary and I support your dissenting opinion if that's your version of reality.