You just asked the "BMW, Lexus, or Mercedes?" question.
Most everyone will reply with a derivative of "how can you lose with any of the three?" and then proceed to tell you about their personal experience with one particular brand (because who could afford all three??? except possibly Chris...).
www.betterviewdesired.com (which is just about as good of a binocular review site as there is on the web) leans toward the Nikon Venturers. Of the three you mentioned, I couldn't help but drop my jaw the first time I tried out a pair of 10x42 Ultravids--the Leica's just radiate quality. I like the ergonomics on the Swaros and I love the color on the Nikons.
But if I had the money, I'd probably buy the Zeiss Victory II's. I have seen no brighter 40mm objective binocular in my experience. The only glass I ever used that gave a brighter picture was a pair of Minox BD 10x58 BR, but you needed a forklift to wear them for more than an hour.
Just my two cents...
Take the long way home.