I still think the "best" device is the one which suits the users individual needs the best. All devices have their strong and week points:
The 1020 is equipped with rather dated hardware. Modern screens are better. While the camera is after all without much competition in terms of quality, it lacks in terms of shot-to-shot performance. People who like to take pictures of moving subjects like their kids and pets keep complaining the 1020 just can't keep up with the playing crowd. On the other hand let's not forget about the powerful Xenon flash which equals those of pocket digital cameras.
You can't expend the memory, if I couldn't have gotten the big 64gig version, I wouldn't have choose, the 1020.
The 1520 is too large and uncomfortable for many people, it also is more expensive. While the hardware is certainly better in every aspect, the camera is not. However it has a much better shooting performance from what I've read, then again it "only" features a dual-LED flash which simply can't reach the power of the Xenon flash.
The memory can be expended via SD cards, which is important for many people.
Same goes for the 930, while it is much smaller than the 1520 while sporting the same hardware, it still is much more expensive and has the same camera stats as the bigger Lumia sibling.
Personally I am annoyed by the fact Glance is not supported. What kind of flagship is a phone which doesn't even support a popular, premier feature of the whole Lumia line?
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