A Linux Tablet

I'm not a coder but a user, loving great software I've come a long way. From Win 95, 98, XP to OS X 10. Now I'm just discovering Ubuntu. Looking at how frustrating it is to use windows, graphs like the following make be sad and I really wonder why people always stick to what you put in front of them.

http://cl.ly/0j1q0H090b2n0l3A1o0M

I don't like where Apple is heading. I don't like being told what to do and how to use my machine and where to buy software. Thus I'm moving some of my work into Linux space.

What I still need in my machinery device park is a tablet to read PDFs while travelling or laying on my couch. I could buy an iPad, but again, I don't like where Apple is heading. I have done little research, but the idea of a Linux tablet sound very appealing to me.

A quick search brings up the company Zenithink and their tablets.

Are there other options on the market? Can someone provide some user experience how those tablets feel in everyday live? Crashes or smoothness? Battery life?

Love to hear your thoughts.