Upcoming Windows 8 Tablets/Convertibles, which is the best?

Which is the best windows 8 tablet or convertible that is coming out?

Sony Vaio Tap 11

Sony Vaio Fit Multi-Flip PC

Microsoft Windows Surface Pro 2

I am a student in high school, I need something to write on (with a digitizer) and type on. These all have digitizers. Currently I have an iPad and a MacBook Air. I am selling my iPad due to lack of use, but I need a replacement tablet to write on. Bringing both of those takes up too much space in my backpack to bring to school. I need something that I can type on and I know that I can type on all three. I like that the Tap 11 and the Surface are small and thin, but I also like that the Sony Fit multi-flip has an attached keyboard, I also really like the looks of it. Which of these three do you think is the best for school?