Seconded. I live in rental apartment and painting walls is not an option for me. I have their biggest size surface stuck to my wall and I love it. The only downside that I found so far is that if dry erase marker writing stay there for a longer time, they do not come off as easily as from traditional whiteboard. But paper towels (and sometimes a little bit of cleaning solution) easily solve that.
If you like moving around with your whiteboard check out: http://www.whiteyboard.com/
You can move it around and wash it and it's fairly cheap.