I've used a couple Diamondback Tactical FFPs, I don't like going really high magnification on less expensive glass (say, over 20x, under $750) as it seems pointless for the last bit of magnification range. I'd take clarity over power every day of the week. Meaning, a clear 16x is way more usable than a blurry 24x. I'm also not a huge fan of most FFP reticles, as they're too small to use at lower mag ranges. I currently have 3 Bushnell FFP scopes since they were on sale cheap, but I've looked through a pile of scopes--and they all seem about the same to ME, in that the subtensions on the reticle is only really legible at the top third of the power range. 3-12 FFP, really only good from 8x-12x, under that too small to make out numbers and hash marks.
I'm no scope expert, but it really boils down to preference. I had a 6-24x FFP Bushnell Nitro that focused down to 10yds, glass was not great past about 20x, and the FFP MOA reticle was not great under about 14x let's say, so I really had a 14x-20x scope. And as far as parallax focus, are you chasing .001 groups with an air rifle at 10 yards where you need the focus that close? At 10yds with a 25yd focus scope, you can just turn the power down and the parallax is just not going to be that big of a deal.
I, and lots of other people just like me, used to do some pretty decent shooting with old 4x scopes with parallax fixed at 100 or 150 yards, before we realized that we were doing everything wrong.
My recommendation is to put your best or favorite scope on the gun you shoot the most! I'm to the point I wouldn't mind a Swarovski or Razor on a .22, but I'm fine with a basic scope on a hunting rifle I may look through for 10 minutes a year.
I currently have a 3-12x FFP, and two 2.5-15x FFP scopes, and the reason I chose those power ranges is that It's easier to have a clear sight picture with lower magnification, and the FFP reticle is usable for me at lower powers. The top third of the range is 8-12x, and about 10-15x for my crappy eyes. I can still use them as a nice fine crosshair at lower powers, clear down to 4x or so.
ETA--PS, I removed my Razor HD-LH 3-15 off of my main hunting rifle, because I got tired of having another knob to worry about, and the slippery power ring. On a hunting rifle, under 500 yards, I decided I wanted a super simple scope, so I went back to a Leupold Freedom 3-4x40 with it's big chunky power change lever. When I'm sitting at a bench, I don't mind having knobs to fiddle with, but on a hunting gun I just want to pick the gun up and shoot.