For what it’s worth…
I was an early-uptaker and have essentially used the 12x NL as my (full size) do-it-(almost)-all solution for about 18 months now.
Picking up on some of the themes already posted, here are a few random thoughts.
I’ve used mine in all habitats at all times of day with great success. The quality of image, 12x magnification, extremely impressive field of view (both actual and perceived); plus combination of ergonomics and the nicely-engineered reliable mechanicals mean that subjects in almost all habitats and circumstances can generally be acquired very quickly. And once they are, you’re most definitely in (not at) the show.
The 12x magnification absolutely does facilitate picking out and identifying subjects that an 8x or 10x would be challenged by. Conversely, even in very closed habitats the 12x NL is still utterly viable. Only when it comes to things like following fast-flying dragonflies at close quarters does the 12x become something of a liability.
I can hold it still enough, but, this has taken some work. I’ve found that experimenting with different grips makes a significant difference. On this point - and as is reasonably well accepted - it’s too simplistic to associate magnification alone with steadiness of image, there are numerous other factors such as weight, balance and ergonomics at play. I can hand-hold my Monarch 5 16x56 almost as steadily as the 12x NL, but there are some 10x’s that I struggle to hold as still as the 16x56. I think the matter of the shakes is a very personal thing and it’s folly to generalise. Simplistically, you need to give it a go rather than rely on the personal accounts of others.
The headrest. Hmmm… I tried it, and as far as steadying the image was concerned, for me it made not one jot of difference. It did, though, make the binocular far more cumbersome and very successfully prevented the casual use of hats. I sold it.
Careful eye placement is rewarding. The 12x is unforgiving if IPD and eye relief are anything other than spot-on. I’ve found that my very personal requirements mean that eyecups screwed out between 2 and 3 stops from the fully-in position almost completely eliminates glare without introducing the spectre of kidney-beaning. I use 3 x nitrile ‘O’ rings to achieve this position. Position 2 = kidney beans, position 3 = glare. Once set up correctly, I can now bring the binocular to my eye very quickly and am reliably rewarded with very speedy and utterly absorbing acquisition.
The case is, for me, useless. I like to be able to get to my bins very quickly without having to fight zips and a tangle of bundled-up neckstraps. The case is in the original box: somewhere deep in storage.
Same with the strap. I wear my bins quite short on my chest rather than have them bouncing off my belly. For me, the (neoprene part of the) strap is too long. Specifically, I can barely adjust it to be short enough to achieve the position I prefer, and even when it just about will go short enough, there’s then absolutely no way it will accommodate the eyepiece cover.
Ah, the eyepiece cover. Much has been written already: it’s just clownshoes. I’ve had to heavily modify mine to make it work in the field. As well as carefully removing the stupid internal indents that mean it can barely be removed from the binocular, I’ve also taken off the strap-guide from the side I don’t tether. This now makes for a snag-free, swift and easy removal / replacement. This is not a fight we should have given the price point and Swarovski’s supposed attention to detail.
Regarding the accessories in general, my own conclusion is that they’re more about gimmick and corporate identity than practicality. In this vein, I must thank Nikon for making simple cases and straps that allow the NL to actually work in the field.
So, in my case anyway, following some experimentation and modification, I’m very happily able to use the 12x NL as an extremely competent and rewarding do-almost-everything binocular. For sure, it’s the closest I’ve come yet to an instrument that I can take to any place at any time and be confident that there are few other binoculars that would make my life better at that precise moment.
Perfect? Absolutely not. Is there much better out there as a do-it-all? For me anyway, probably not.
If anyone from Swarovski is reading and would like to reimburse me for the strap and case I’ve had to acquire to make your NL work then that would be nice. You can have yours back.