I've owned the 10x42 SE, and I've tried the 10x42 SLC HD (first version with the two colors and shorter close focus).
10x42 SE
PROS:
-- very sharp, 3-D view
-- smooth if somewhat thin and slow focuser
-- comfortable ergonomics--although some people prefer the elbows down ergonomics of roofs, the SE's prism housing (common to all three models) fit my hands like a glove)
-- field flatteners (takes a bit away from the 3-D effect but still way better than roofs)
-- very high light transmission @ 95%
-- long eye relief
-- lightweight @ 26 oz. (allbinos list them at 28 oz, but I think that's wrong)
-- well built for a porro, but don't drop them
-- contrast is good but remember the 10x SEs were the first one's made by Nikon. Early production runs whose serial # stars with 0 do not show as good contrast as later runs whose serial # stars with 5.
CONS:
-- not waterproof
-- has wide and deep rubber eyecups that were not made for European faces. The eyecup height can't be easily adjusted, though I have seen some owners use a rubber band to get in between all the way up or down, however...
-- prone to image blackouts when you pan or if your eyes sink in too close to the EP lenses
-- has some CA, less than many non-ED roofs
-- the FOV is a bit cramped comparatively @ 6*
-- despite the great ergos, I found it harder to hold steady than the 10x35 E2, perhaps because of the weight vs. size--I used it with a weight hanging from the central post, which made it easier to hold steady
-- long close focus
-- red bias can make the image seem darker than you would expect for such a high transmission
10x42 SLC HD
PROS:
-- bright views, high contrast, vivid colors, though not quite as sharp as the SE
-- very good edges ~ 90% -- achieved without field flatteners
-- comfortable ergonomics although not as comfortable in my hands as the SEs
-- although the listed FOV is only slightly larger than the SE, the apparent FOV seemed noticeably more open
-- high light transmission, not as high as SEs, but VG for roofs
-- long eye relief
-- waterproof and fog proof
-- very robustly built--will survive being dragged through the mud, the blood and the beer -- a hunter's delight, but it's also suitable for 10x birders with strong arms...
CONS:
-- weight @ 30 oz was too heavy, and since that weight is not widely distributed like the SE porros, but centrally concentrated in the two parallel tubes, the SLC feels even heavier, hurt my neck and shoulders after an hour's use
-- the focuser turned smooth toward the left and harder and sticky to the right (like all Swaros, not to my liking)
-- eyecups were comfortabe for my face like, similar to the Nikon EDG
CONCLUSION
Ultimately, the uncomfortable eyecups were a deal killer for the SE (for some it's the image blackouts, but if you roll the eyecups down and use the SE with glasses, you might not have this problem).
The heavy weight and focuser were non starters for the SLC.
I think a better choice would be the 10x42 EDG, which obviates the above issues.
Is the SF also 10x42?
