Microsoft has unleashed its cavalry in the battle of big tablets in the form of the Surface Pro 3, its most impressive and desirable tablet yet.But is it enough to draw the eyes of the masses from the iPad Air and even the Samsung Galaxy Note Pro 12.2?As phones continue to get bigger, the same is true for tablets, and the space for 10-inch plus slates is getting more and more crowded.So which big tablet has what it takes to beat the other two?SizeSamsung's Galaxy Note Pro 12.2 is the largest table in terms of sheer size, at 12.2 inches - .2 inches larger than the 12-inch Surface Pro 3. The Note Pro is 7.95mm thick and weighs just 750g, 50g less than the Surface Pro 3's 800g. The Surface is also thicker at 9.1mm. Meanwhile the iPad Air measures 9.4 inches and 7.5mm thick, making it the thinnest of the three tablets. It weighs just 469g as well.