NO NO NO
Unless things have changed very recently, these things have not been cleared for fast jet use and I am sick to death of jets being grounded, taking up valuable time and resources, because some jockey has taken his nice shiny 'un-cleared' knee board into the cockpit only to find that bits come of it / it disintegrates and becomes FOD a little too easily.
Please check it has been cleared for use before you buy one, because us engineers have enough to do without any old kit being taken into the cockpit.