"Best" how? Easier to use? Better optics? More durable? Other?
Having wasted/invested bazillions on binoculars over the past -- gee whiz, 35 years?
-- I concluded the following were important for me, in this order.
1. Optical quality. This includes quality of lenses, [any] lens coatings, alignment of barrels.
2. Durability. This includes type of optical glass, type of lens coating, strength of pivot for barrels, material composing barrels' housings, type of diopter adjustment, and type of binocular design.
3. Comfort. This includes range of diopter adjustment, quality of barrels' alignment, weight of binocular, ease of use with spectacles.
4. Ease of use. This includes how easily I can adjust eye pieces, any bells & whistles not included elsewhere.
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Binocular I use NOW -- I have two -- is Zeiss 8x30 B/GA IF Olive, with F2 range finder and drop-on snow lenses. This binocular was developed by Zeiss-Wetzlar in 1964 for NATO use by German Army. It has roof (Schmidt) prisms, rubber armor, with individually focussing eye pieces, and roll-down eye cups. They weigh 23 ounces, about 25 ounces when the top and bottom lens protectors are included.
This binocular is no longer available from Zeiss-USA, except via special order. It is still available in Europe.
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My experience shows me that Schott optical glass (Zeiss subsidiary) is more scratch resistant than glass used in Japanese optics. How important this is for you is your decision.
Lens coatings are a problem if you worry a lot. My experience is that German (Zeiss and Leitz Trinovid) coatings are more scratch resistant than Japanese, but this is a small difference. External surfaces' coatings degrade when you hunt. You cannot really avoid this on external lens surfaces. Live with it.
Top quality binoculars appear to be comparably well assembled when made in Europe or Japan. How long a properly aligned binocular remains aligned is very important. You will be using your rifle for about 10 seconds; your binocular much of the remainder of your hunt. A binocular that gives you a headache, or cannot discriminate details is worse than useless.
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Here is a good place to mention Chinese stuff. Do you really want to buy a product made under conditions where no American worker would want to work? Slave labor is cheap. It delivers cheap, too.
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Individually focussing eye pieces allow more durable binocular design than central focus. Is this important? Hunters tend to focus near infinity then look and look. Changing focus is less important than for birders, in my opinion. Note that military issue binoculars are IF.
Porro prism aka Zeiss "E" body design has objective lenses farther apart. They give better depth of field than roof prism aka "H" body design. Porro prism designs also tend to be heavier, less durable over time, and less expensive to manufacture. Porro prisms require BaK 4 lenses for best quality. Roof prisms have no such requirement.
If I were on a budget, I would look first at military surplus porro prism binocular that had been made for NATO use.
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You must remember than a binocular is really two telescopes assembled to function as a single unit. To have this assembly function correctly for many years costs MONEY.
A superior warranty is not nearly as useful as durable design. If you're in the field and your binocular craps out, how useful is the warranty? But money that goes into durability -- that pays immediately.
The way I look at a binocular purchase is that it is a lifetime investment. Excellence now will remain so in 30 years. So the cost of owning the best available binocular, when you amortize the cost over your lifetime, is peanuts.
This pays several ways. Your binocular retains its value. Look at prices for used Zeiss Classic roof prism 7x42 or 8x56 binoculars. Unfortunately, you will find few of my binoculars on the used market.
Your binocular will function no matter where you are, no matter what the weather.
Lastly, there is pride of ownership to have THE BEST. The best can become your son's or grand son's, and they're still THE BEST.
Hope this helps.
