I needed a scope for occasional birding, and to carry in my rucksack when hiking. It's main use is on coastal walks as a high powered alternative to binos, so portability and weatherproofing were important.
The choice of scopes is more bewildering than binos, the market segment is smaller and there is a lack of impartial reviews, so I visited my local optics shops in Bath, UK. My preference was for a straight scope rather than the 45 degree angled, since it is easy to sight either by hand at lower magnification, or to follow movement when on a tripod or monopod, and high angle viewing was not a consideration. I was not going to be using it for digiscoping and so the lack of a removable or adaptable eyepiece was not an issue.
My budget at @£350 limited my choices. The Nikon scope was a mint condition used buy still boxed so fell within my price range. The design has apparently been around for quite some time and there was a Mark 1 version of the scope about which I can find nothing other than that it was popular with shooters and archers as a range spotting scope. I spent an hour comparing it to new offerings from Barr & Stroud, Celestron, Olivon and Avian, and used Optolyth, Opticron 66HR, and Nikon RAii, scopes. The instant I looked through the Nikon XLii I was struck by the very much brighter and sharp image compared to all the others right through the x16-x48 zoom range.
The scope is very different in construction to all the others I tested - More a traditional telescope design. A good description in order to convey the build quality would be like a rubber covered metal Mag-Light torch. In fact you could clobber someone with it and not worry about damaging the optics! It is about 320mm long and weighs about 800 grams, so will easily slip into a rucksack. It has a nice padded zip around case with a clip on/off shoulder strap that fits snugly and acts as a stay on case when tripod mounted. The scope is completely waterproof with a thick rubber jacket and with a push in rubber lens cap (very firm) attached by a rubber tongue to the sliding hood of the scope, and an all enclosing end cap for the eyepiece which is a very snug watertight fit, all fabulously engineered, solidly made and I believe the claim that it is waterproof to 2m for 5 mins. One US review (one of very few I could find on this scope) berated the Chinese origin, but this is unwarranted as the build standard is right up to normal Nikon high standards.
The eyepiece is like that of a traditional telescope, and is metal/alloy with a hard thin rubber "washer" to prevent scratching to glasses. I am a specs wearer and was able to view comfortably with glasses on and not loose field of view, my eye position is different w/o glasses and with contact lenses but it is easy to get a comfortable distance to get the optimum view. The zoom control around the eyepiece is quite stiff but does ensure it does not shift unintentionally. The focus on the eyepiece moves sweetly, though at maximum x48 magnification the adjustments using the ring need to be very fine indeed, though this is normal for zoom eyepieces. The max magnification image darkens from about x40 to x48 a little but noticeably when the light is poor but in good light the image is sharp at max magnification notwithstanding the fine focus adjustment that is required. Of course these points are a trade off against the portability of a 60mm objective lens scope, and of a zooming eyepiece. Nikon's lens coating certainly does a good job in providing a bright and contrasty image to my eyes, and on a warm day is less affected by heat haze than the image from and 80mm+ scope.
I have found the ideal hiking combo is to have a monopod to mount the scope on. This ensures a quick set up in the field. By wrapping my left hand and arm around the top of the scope and placing weight on the monopod, I could hold the combo very acceptably firmly to view up to about x35 magnification. Using a tree or rock as an impromptu support for the scope for your arms works comfortably up to all but the very highest magnification also and is quicker. The armour coating ensures that the scope is not damaged by such a support as well as ensuring it does not slip.
The bottom line is that I am fussy about image quality, and the Nikon Spotter delivers top image quality for this type of scope. Image quality is of course always subjective, and it is a trade off against price and portability. It is not a dedicated birding scope in the sense that such users would select a large objective lens and be less concerned with portability in order to get the highest image quality for their money as well as digiscoping capability. Neither will it sway those with the pockets for Leica and Swarowski scopes. The Nikon Spotter is more about convenience and quick set up in the field, or for use in rugged conditions or in the wet. As you can probably tell, I really like it. I wrote this review as there was very little information about the scope online. I am glad to have actually had an example in my hand to compare to other scopes, before buying, but hope that my experience with this scope might help others with similar requirements to consider it also.