Here you have to decide whether to 8x20 or 10x25 preferred initially.
My choice fell on 8x, since it is a bit small and you need to be holding the hand a lot quieter at 10x, which is quickly noticeable on strenuous hikes.
The 8x20ern I took in the selection:
Zeiss Victory
Leica Trinovid
Swarovski Pocket
Nikon HG
The comparison test lasted for 2 weeks and the time it took to identify the significant differences in quality as glasses, which are mainly in many cases on paper. For example, the small differences of these four in the field of view size and the minimum focusing distance in practice affect barely.
The first difference you notice when taking into their own hands. Here the Swarovski has been using an exclamation point. The others are not bad, do not come far but at the Qualtitätsgefühl the Swarovski already with the haptics conveys ran.
When handling even Leica has the edge. Not only the smallest pack size and best stowed in the pocket, but also the arrangement of the elements, resistance of hinges, attaching, viewing distance ... Here you realize the experience of Leica. Swarovski can most likely keep up, Zeiss and Nikon are clearly worse, without however being really bad.
The longest it takes the differences in the assessment of optics perceive. Who only knows far simpler models in this size, is immediately impressed by the brightness, clarity and detail. In terms of brightness, these four glasses give nothing.
As for clarity, detail and presentation are neutral Nikon and Swarovski forward.
Closely followed by Zeiss, which is minimally worse under an overcast sky and mirrored surfaces and Leica, which has slightly less edge definition, however, is noticeably more prone to flare.
Nikon, Zeiss and Swarovski are as waterproof, Leica given as splashproof. I could not test this, unfortunately.
Conclusion Nikon High Grade.
Small, waterproof, optical top notch. Light compromising the handling, but meanwhile also the least expensive of the models mentioned. The hinges should not be the most stable in case of falls, 10-year guarantee, however, are a reasonable confidence.