Many of the questions in this comments thread (e.g. safety, e.g. vertical mounting, e.g. cost associated with the bearings, e.g. the basis of the 7% figure) are already answered directly or indirectly in a year-old Q&A article that was linked from TFA.

http://www.extremetech.com/computing/90272-the-fanless-spinn...

Not very good-HN-citizen-ish to post questions without putting any work at all into looking for the answers, is it?