I had both for a while and a Kowa 554. I did some fairly objective comparisons and included the link that discusses them (thread was about 18x binos but have some small parts about the spotter too). It has low light and edge to edge clarity comparisons in the link.
Also attached is a resolution chart comparing the three. Obviously their zooms are all a bit different but you'll get a feel for how they compare. Charts at 400yds in overcast skies.
General consensus is I like all three and they each have trade offs.
Weight. Kowa 8oz lighter than GR which is 8 oz lighter than Razor.
Length. Kowa is shortest. Close to GR (fatter though). Longest is Razor (only by a few inches).
Glass. The Kowa is the best. But has limited FOV and eye relief. The GR is about the same as razor IMO. The eye relief in GR is massive.
Ergonomics. I really like the finger tune focus (Kowa and Razor). I think the focus on the GR is stiff and tough to view and focus at the same time.
BL: I stuck with the razor. I like the focus the best. I got the LER 22x lens for it which was cheap and works well. And I got it for $575. Compared to $1000 for the GR and $1400 for kowa. All three fit in my pack and I didn't mind having an extra pound for the weight for the cost savings. I also like the 48x zoom. According to my chart with my eyes it did matter. Also in edge to edge the sample I had was nearly perfect. I am happy with it.
Many will say the GR is arguably one of the most well balanced spotters out there though. Another one Rokslide folks throw out a lot is Athlon Ares 15-45x65. I'd get the first gen on that one though because it's more compact and lighter.
Hope it helps.
Folks Doesn’t seem like too many have had hands on the UHD and Maven 18xs together yet. Had the chance to demo so will give it my best shot at comparing. That said I will draft a couple initial posts and then encourage folks that have specific questions to reply and I will do my best to get...
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