I've had five FDNs and still have 3. To my eyes they resolve targets a smidge better than my ATACR 7-35 at distance. My only complaints I can come up with are:
- The 25x has a tight eyebox (52mm objective). Less of an issue with the 17x.
- The 25x minimum parallax is 75yds
- The turrets are difficult to actually understand vs the set screw types that are common these days. The ER3K zero stops can be hard to understand, and the center screw that lets you move the erector independently of the turret position is confusing if you don't understand the design.
- The FDN 10x's reticle is just too thick. They should reevaluate their reticle designs in the 10x to at least offer the MHR from their TS line. I'm a big fan of floating center dots.
- Low light performance isn't anything special, especially on the 25x with the 52mm objective.
Like Jake said, the B-Series had issues with people over tightening their turrets and stripping. I had considered buying one used, and called USO to ask about warranty coverage on the B-Series, and what Kyleigh told me is that they launched with aluminum internals on the B turrets and had issues. They switched to steel later on, and the issues went away, but the damage had been done and they went back to an updated EREK design (ER3K) that featured a zero stop, but did away with the locking turrets and tooless zeroing in the B-Series. Kyleigh told me that if I bought a B Series here on the hide and it had issues, they'd take it in and replace the turrets with FDN turrets, free of charge, as part of standard warranty servicing.
A lot of people had bad experiences long ago, and justifiably steer clear of the brand. I won't blame them. I'm never going with GA Precision again, despite their customer service being stellar, and my experience likely being a unicorn nightmare. I get it with guys never going back to USO. In the mid 20-teens it seems like USO was the cheaper alternative to a S&B for an FFP scope that could track, until Nightforce's ATACR series started to take market share along with the Razor HD II and K624i.
My gunsmith and another shooting buddy both run Razor 3s, and when I let them get behind my FDN 25x at 20x power, they couldn't believe it was only 20x. The eyepiece is closer to your eyes, and I get the same amount of information at 18x that they do with their Razor 3s at 22x, but with more FOV. If you watch C_Does' reviews comparing the MR-10 to a Leupold MK5-2-10 and pause it when the scopes are both at 10x, the picture that comes through (and he compares scopes at the actual eye relief and doesn't crop the pictures to match) on the USO is legitimately 25% bigger than the Leupold. While on paper, the scopes have equal magnification, what you end up seeing is far, far different. People like to dog on the tunneling at low power, but they're surprisingly more forgiving of the S&B PMII and ATACR series despite their having the same "shortcoming".
Jake Vibbert, Brett Barnes, and Ken Sanoski have won a lot of matches with USOs in the last few years. You don't win matches with gear that doesn't work. People like to b!tch about Leupold tracking issues and MK5 horror stories, but the amount of guys winning matches with MK5s shows that they're capable optics regardless. And that's coming from me, an avid MK5 hater. Again, you don't win national matches with gear that doesn't work.
