Nikon Action Ex Extreme (10X50) Binocular

I collect and repair moderately-priced binoculars and telescopes, and this is my favorite, for both land viewing and astronomy. Brilliant sharp images; Nikon's camera expertise (e.g. lens coatings) really shows. They're good at night, better than 7x50 "night glasses" for reading license plates etc. It's my only binocular not intended primarily for astronomy that still shows stars as sharp points instead of little blobs. I found Neptune and Vesta (the asteroid) with it, and Andromeda looked just like a galaxy should.
The aspheric lenses are mathematically more complex, to give optimum performance compared to old-fashioned spherical lenses, especially a 1/3 wider field of view.
Like most well-built 10x50's, it's a bit heavy if you don't need the power. I'd recommend buying wide spongy straps, to avoid neck soreness. And at 10x you need fairly steady hands, or a tripod is nice for fixed viewing. But I often use it an hour or more at a time, pointing up at the sky, without much fatigue.
Alignment on my smaller Nikon 7x35 was a bit fragile when dropped, and this may be too, so I'm careful with it. If you do drop them, re-alignment usually just means tweaking 2 tiny screws under the body rubber just beyond the eyepieces. Or find a binocular alignment/collimation expert if nothing actually breaks.
As others point out, the lens caps are a silly design, fitting inside the tube end instead of outside (they fall off easily), and the case is soft and has no straps (but is lightweight). Minor annoyances, but unnecessary.