Summary: ORIGINAL REVIEW: Do not buy this lens for a Sony NEX 6! In theory, it's just fine, and it worked fine when I received it, so I set it aside for an upcoming vacation. The first time I tried to use it in the field, though, the camera would not recognize the lens, would not focus, and would not shoot. Google the thread "sony nex 6 lens not recognized" and be warned. The lens is apparently made loose and the contacts don't connect well -- at least to the NEX 6.
Excerpt: Sony doesn't offer, as of yet, a hi-end long e-mount telephoto for their nex system. Because I like the compactness and autofocus capabilities of native lenses I bought this. It did not give me the color pop or contrast of other lenses like Sony's 10-18 ultra wide zoom, Zeiss 24 prime or Sony 50,1.8. Autofocus is slow. Don't expect to use this for sports or wildlife unless the subject is stationary. However, the images are reasonable. I'll continue to use this lens.
Summary: I flatter myself that I'm an "advanced amateur" photographer for over 50 years. I'm quite used to Canon DSLRs and their lenses, and to Sony E mount prime lenses. I really wanted this lens to work, because the focal ranges were exactly what I wanted. I spent many hours and hundreds of exposures trying to "learn how to use it" - but in the end, I returned it, because I could not get an acceptable percentage of "keepers" with the 55-210.
Summary: While I enjoy using this lens, it's soft at 210mm. At first I thought I had a defective copy, but the reviews seem to say this is a common issue. It's still a decent lens, but the softness does limit it's usefulness for wildlife photography.
Excerpt: I use this on a NEX-7 that I bought to use as a digital back for my existing lenses. There is significant fringing past about 150mm. I'm not really a zoom shooter, but I have been accompanying my wife on some birding expeditions. She uses a little Nikon P510 that generates much, much better photos than this lens on the NEX-7.That said, these NEX lenses are great for video, where the performance at the widest apertures and maximum extension are not as critical.
Summary: What I wanted was a case that really fit this lens so that I can pack it and not worry about it bouncing around. This bag is a bit too large, so the lens moves around freely INSIDE the bag, which makes me nervous. I'm using it, because I can't find anything that fits better. If I find something that fits better, I will definitely stop using this.