Not sure where they're going with the iPad and don't get me wrong, it's good at strict consumption, but for productivity it's a stillborn. Hitting a flight tomorrow for a long trip. I'd much rather have one device like the Surface... not even a laptop... I get the best of both worlds.
So get a Surface. If that fits your usage, then that's what you should get. Me, I prefer my tablet and laptop separate. Surface is too small for me to use as a laptop, and too heavy as a tablet. Perhaps if I traveled a lot, I'd want something like the Surface, but I don't, so I like my laptop to be 13 inches, and my tablet to be thin and have a more squarish aspect ratio like the iPad, rather than the longish ratio of the Surface.