Milling or ranging with either FFP or SFP has been replaced, by most part, by laser range finders. If the degree of accuracy doesn't require an 500 cold bore head first shot, such things as Leupolds BAS work pretty good, and has been around for quite a while.
FFP in the US "caught on" about 2000 and with it and some other things scopes say an incredible improvement, in all areas. Have been using FFP Swarovski 2.5x10 PH with German #4 since they came out, and they were great scopes for hunting.
SWFA got going before either Sightron or Vortex and they simply remove the middle man to give the buyer a better deal. All their scopes are built to take a 50.
Their MilQuad reticle was a result of several market "forces" that occurred at that time. US Optics had the ability to design any reticle you want and the one designed by GAP precision rifles was very popular. As a consequence IOR jumped on the wagon with their Snipershide edition and a short time later SWFA came out with the MilQuad.
Using FFP on a 1x6 or in that range has the advantage of making the holdovers "disappear" at low power , and very "fast" on target as in a 3 gun match as an example. and on the higher power the "hold overs" come into view.
Most good SFP scopes can be dialed in at any magnification with good results, and you can "cheat" by reducing the power to "lift the barrel" for extended distance such as the BAS system.
Most good SFP scopes with hold over reticles can be "tweaked" to gain/lose MOA or Mills even at the hold interval for greater accuracy because they have very good parallax correction.. NF bench are an example.
most hunting type shooting is area shooting
few shooters run box tests or tall ladders to see if their scopes do "track" or even hold zero, let alone how long they will do it. ( over a number of rebarrels on the same action and stock)
The biggest advantage on the higher power variable FFP is exactly that you can make the reticle small for close shots or if time/setup allows bring more information into the view by dialing up. This has advantages in changing light.
SFP scopes reticles must be designed, and their "density" as a compromise.
Everyone has their pet peeve on scopes. Mine is advertisements that say or used to say Nitrogen filled. Hmm isn't air something like 60% nitrogen.
