I sometimes wonder how much I "need," mag wise. I guess if the scope can really deliver it well, it's moot and you want as much as you can get. I didn't necessarily feel like I needed more than 18x when shooting to 1000 yds...but, then, I'm not an objectively good or experienced long range shooter, either. Perhaps I totally misinterpreted it, but I spent some time tooling around on the Primal Rights website a while back. When shooting at 100 yds, I can tell you that when I dialed my magnification back my groups got smaller. Now, it could be that I'm also getting better as a shooter, so I'm not prepared to say unequivocally that it helped...but, I am pretty confident it didn't hurt.
In a general sense, 3-18 is my "happy" zone of magnification IF the scope can deliver at 18x. Based on what I've read here on the hide, it seems like a lot of optics struggle once you dial them past 75% of max. Again, that might be a bad read or confusion on my part, but in some sense I've been chasing 24x on the top just to get 18x that "work." I know that leaves me out of touch in a world where people are rocking 5-30, 7-35, etc. Perhaps I'll get into something that leaves me wanting for more magnification or it will just happen over time.