Well, I’ve had them both for a few days now. It has been a couple of weeks since we’ve seen the sun, so all of the outdoor observations have been in gray overcast situations. There is not a lot of difference I see in the Promaster ELX ED and the ZEN ED. The ZEN is a bit brighter, but this is a small difference. It does not seem to affect the sharpness or what the image shows in detail. It may well be a function of the Repellemax coatings of the Promaster. The ZEN offers no repellent coatings. I’ve used the Promaster in the rain, and the coatings do work. The Promaster has a violet tint to the coatings, the ZEN is green.
The ZEN ED 8x has a little more than a half-degree in fov, 426’ vs. 393’. Both fields are pretty wide for the 42mm class. The ZEN and Hawke are at the top of the heap. The Promaster is about the same as the EL. The Promaster has a smooth gripping surface; the ZEN has a nicely stippled griping surface. The ZEN is a bit shorter than the Promaster and about two ounces lighter. The ZEN has a bit more sophisticated, or perhaps a better finished, feel. The ZEN also has more streamlined eye cups which will suit those with smaller faces, smaller eyes, or more deep set eyes. It will be interesting to see if the Promaster evolves a little with what look like they might be some small progress in improvement.
For wide field binoculars, they do a very good job of producing a nice flat field, with minimal, or at least very subtle edge distortions in the outer edge of the field. As far as I can see they do a very good job at control of color aberrations.
Now as to comparison to the top glass, I have compared my 8x42 Promaster to the Swarovski 8.5x42 EL. Steiner Peregrine XP 8x44, Zeiss FL 8x42, Leica Ultravid 8x42, Meopta Meostar 8x42, Bushnell Elite 8x43, and Vortex Razor 8x42. Of these I think the Promaster has a superior image to the Meopta, in that it does not have as much of the Meopta yellow tint, and it is a bit brighter in appearance and sharper than the Bushnell Elite and the Razor. It is less bright than the Zeiss as well as the Leica. The Leica does not seem as bright as the Zeiss, but seems to have a more neutral color tint and maybe a bit better color contrast. Put the Promaster ELX, the Swarovski EL, and the Steiner XP on a tripod and you (well most people anyway) have your work cut out to distinguish the three. Eventually, I placed it Swarovski, Steiner, the Promaster. None of these three are quite as bright as the Leica or Zeiss. Looking at a resolution chart really does not give any of these binoculars either a clear advantage or disadvantage. What there might be I think is largely un-noticeable unless all are right there for comparison.
Now, I do not think either of these will pass a thorough professional optical exam with the same sort of scores as the alpha class. We are talking about silver coated prisms vs. dielectric coated prisms, and probably technically better glass and broadband multi coatings, so direct equality is not likely in the cards.
About the only nit pick that I really have is the slow focus wheel rate. It requires a bit over two turns, but a lot of that is used focusing in closer than about 50 feet. A quicker focus speed will have a certain appeal for close in birding and butterfly watching. Get much past 60 feet or so and the depth of field is good enough you don’t need more that a small tap to move the wheel.
So, this puts the Promaster, and I think the ZEN ED (for me at least) about in the middle in this bunch of optics, which is not bad company to be keeping, especially considering what these cost. They are also clearly better than the mid priced Vortex Viper and Fury, Nikon Monarch, and Pentax SP. But the differences are not great, so if you are happy with your Viper or Pentax, there probably isn’t much need to rush out for one of these.
Is there a practical difference? I don’t think so. I have spent some hours with them and what one will resolve, so will the other. I would place them both in the same relative ranking as I put the Promaster above. The view through these sort of diminish (not eliminate) the “WOW” factor associated with the alpha class binocular and replace a lot of it with “WOW look at what these things do for 1/3 of the !@#$% price!”
I have sort of come to the conclusion that unless you are an obsessive (OK, I guess obsessive might be a bit harsh) optics nut, or unless you need optics in earning your living, or use optics very intensively for whatever your reasons, or unless you simply want, and can afford, the best tools for the job, you probably are not really in need of $1,500++ binoculars. But for more mortal eyes and limited budgets, you cannot do yourself any better than to order one of these. I have both 8x and 10x and all comments apply to the 10x ZEN as well. I will likely buy the 10x review sample. At this point, the ZEN and Promaster give me all the optics I need.