To break up the wall of Youtube a bit, I find that this is one of those genres where the line between brilliant and rubbish is very fine. Like, you say "I like X" and someone says "oh, I like X too. I also like Y" and you think "urgh, really mate, that shite?" It's hard to pin down why - maybe it's because that sort of "tune in, turn on, bliss out" vibe is so, so close to straight self-indulgence, and some of it has some property that elevates it above that but it's quite hard to pin down exactly what it is.
(Droid is now going to neatly pin down exactly what it is...)