Ultravid 8x32 by far. The reason for this is mainly that the 8x32 configuration strikes a good balance between portability, optical performance and ease of use.
Same would be true of a 7x35. I used to have a pair of Retrovids and really liked the view. However, apart from some mechanical deficiencies in my sample, I never felt comfortable chucking them into my rucksack.
I do appreciate larger apertures and exit pupils but when I leave the house I leave them on the window sill more often than not.
I happened across a NOS pair of Zeiss Victorys recently. I used to have a pair a couple of years ago and have always regretted letting them go. Time will tell which 8x32 will prevail as the most used pair. The Victorys seem more robust and have a better panning behaviour but the Ultravids have much nicer colours. Here they are in juxtaposition. The Leicas may seem larger but they are not; it's just the perspective or the lens I used.
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