Just had these arrive and am having a lot of trouble adjusting them so that I'm not getting double vision. The simple thumb screw for each lens is merely a lock - doesn't "travel" to adjust focus like actual binoculars, and so you have to slide each lens physically from side to side to try and centre them on your pupil. The fit of the rail on one lens is quite loose and skitters back and forth too easily when trying to adjust, whereas the other other lens binds, meaning I have to take the set off and use two hands to get it to slide. This is not making for ease of use. I have managed only once (in 30 minutes) to get the two lenses to align properly, only to find out they were each so far off to one side I was unconsciously turning my head about 15 degrees from centre. Still fiddling and hoping I haven't made an expensive mistake.
I should note that during my brief moment of clarity the optics were amazing, so I really hope I can solve the adjustment issues.
The ear piece "wraps" are also very tightly coiled; painfully so (and it's not like I've overly large ears). I'm leery to try and uncurl them to fit properly until I've solved the focus issues, as I may have to return these and don't want to physically alter them to any great extent.
All in all, not nearly as pleased as I'd hoped to be, especially for the price.