FWIW, I use a 5-25x USO Mil-Gap reticle on a DTA HTI .50BMG. Sure, it's a bit fat at 25x for my liking, but it's a solid scope for a .50, I like the reticle for the most part and I have a 17x identical to this one in all but size/power on an SR25. They're also "tactical" rifles. So lower mag, ranging at all powers and tougher build win over other considerations (and I got 'em for great prices on here). If I shot in BR competitions or from rests I may want a higher power SFP with a super fine line reticle. For KD ranges and sterile shooting, why use anything else?
Still, I'm thinking of replacing it with the 7-35x too (I did get it for long range) but I do need FFP, plenty of FOV even at 35x, plenty of elevation and of course, I'd like a thinner reticle than the one I have. I'd also like to be able to use the reticle for holdovers more accurately than with the Mil-Gap and without adjusting knobs every time or eyeballing it, but those busy looking reticles have always put me off until I got a much smaller, older Christmas tree USO 1-8x style and realized it's value..
Only reason I'll replace it though with 7-35x is if it meets all these requirements plus can be used with clip on NV and thermal. It's really gonna have to bring a lot to the table and be a quantum leap over the USO or I have no reason to replace it.
When I was first looking for scopes for this rifle a couple years ago, I looked at the March something-to 40x. All looked nice, but elevation was to be lacking and FOV was deplorable. Granted at extreme distances this won't be as much an issue, but I won't ALWAYS be shooting it past a mile. I need some flexibility. Looked at the BEAST but price just kept going up and up, then it FINALLY got released and I went ahead with the USO due to price anyway after all that waiting.
The S&B 5-30x just looks to be the absolute shit, especially considering it's also small (IIRC and that model comes compact). Actually peerless at the moment. Very expensive, but it seems worth it if you can swing it and I definitely plan on going with one compact S&B high mag optic for a McMillan .338 I'd like to get some day.
Not worth skimping on optics and lower power magnification is generally better than higher power magnification, but that depends on several things and it's up to the user. BR shooters like to use the highest power SFP optic they can get because they have very thin lines at high mag and that's about the only setting they use it on it seems. A tactical rifle, on the other hand, would be hindered with an optic like this IMO. So it depends on what you plan on using it for too.