Interesting comparison. Shows the Lumia 2520 gives more for your money, plus microSD, USB. Still, the iPad Air is lighter (478 g vs. 615 g) and thinner (7.5 mm vs 8.9 mm), + of course a far more complete App Store. Yet, this comparison shows a possible justification for RT 8.1 devices such as the Lumia 2520 and the Surface 2. And here’s another comparison of these three devices.