Kno is one of those apps that was iOS only for a long time, but now includes the Note 10.1. I also would say the Surface would be the best choice, although it's also the most expensive. I would have to respectfully disagree that the iPad is more functional for school. I get what you're saying about the apps and formats and such but I use the Note 10.1 for school and every single thing i've needed to do, there's been an easy way to do it. I might have to do a Google search or something, but I find the answer quickly and it works. Also like you said, most app developers are starting to see the value in Google and beginning to incorporate them into their future (and some, current) plans.
If you have substantial note taking, the Note is amazing for this. The multitasking and split screen is actually very useful as well being on a larger screen. Again though, i'd wait and see what the next iteration of the Note brings. I could see the iPad being a better choice if it wasn't for the S pen. That makes it a whole new ballgame when it comes to school.