I picked one of these up several weeks ago, it’s not bad but it’s not good either. A lot of people seem to think that the base goes under the mattress, not under your pillow, which is amusing since the pole is not at all long enough to clear your head if so. The Amazon reviews are a hoot.
I think it would actually be better if that were the case, as it tends to tilts forward under the pillow.
That said, it does work as advertised, and it is handy for those times when you want to read or watch something on your tablet while lying flat on your back in bed.