I have owned a Swarovski 8x32EL SV ("Swarovision") for several years, and thus feel reasonably qualified to offer a well-informed opinion regarding its performance. However, much has been written about this binocular on BF and elsewhere, so I don't feel a need to provide an in-depth analysis. That said, it is an outstanding glass with no glaring faults (however, like a number of BF contributors I feel that Swarovski focus mechanisms do not perform to the level of other offerings within the alpha class). The 8x32EL offers a reasonably bright image with excellent sharpness to the edge of its wide, flat field and with good contrast in a lightweight package. Eye relief is generous, and I cannot recall ever having noted any measure of chromatic aberration, although I suspect I'm not particularly sensitive to it. It's a rather long binocular compared to the 8x32 offerings from Leica and Zeiss, but not so much so as to be considered a major deciding factor IMO. I'm a proponent of open bridge designs for their ability to offset any perceived or real disadvantages. Simply put, the 8x32EL has provided me with countless memorable viewing experiences. You cannot go wrong here IMHO.
Regarding the Zeiss 8x42SF -- I recently had an opportunity to "test drive" the latest iteration (w/all black armouring) but wish I hadn't. Why? Because the view can only be described as celestial, even revelatory, so much so that I now want for one. It was indescribably bright, pin sharp and provided what others have characterized as a "picture window" view. Granted, this day was bright and clear, so I obviously didn't put the glass through its paces regarding brightness under overcast skies or early or late day lighting situations. However, I would offer that given Zeiss's reputation for seemingly engineering their sports optics for brightness (at least since the FL was introduced [nearing 20 years?]), I suspect it would perform remarkably well. The focuser was almost effortless and silky smooth. My only minor gripe noted during my brief use was that the optical tubes are much longer than the Swarovski 8x32EL and my first generation Zeiss 8x32FL. I'm admittedly comparing apples to oranges due in large part to the Zeiss having 42mm objectives (perhaps a better comparison would be between the Zeiss 8x42SF and the Swarovski 8.5x42EL). However, despite its length, the Zeiss SF was very comfortable in that -- open bridge aside -- it felt extremely well-balanced and light, echoing what others have suggested elsewhere. It's apparent that Zeiss put a great deal of thought into the SF's ergonomics. I can say with confidence that I would not hesitate to carry the SF on long treks despite my long-held preference for more compact optics.
As you likely know the Zeiss SF is priced in the stratosphere given its comparative newness and place in Zeiss's top end Victory line. If you're willing to buy used you'll likely find a Swarovski EL for much less given that it has been in the marketplace for a number of years. If I were in the market for an 8x binocular and cost was of no concern I would likely purchase the Zeiss 8x42SF over the Swarovski 8x32EL. Again, my experience with the Zeiss SF was brief and subjective, not at all what would be characterized as scientific or thorough. One cannot really make a mistake from an optical performance standpoint when purchasing at this price point; how the ergonomics of a particular binocular play to one's vision, facial structure, hand size, etc. are often the deciding factors. The advice to try as many optics as possible prior to purchase is repeated ad nauseum and for good reason.