Thanks, yes that WAS my opinion of this genre generally (and still is my wife’s opinion). At their worst Mushroom veer in that direction but they seem to have almost endless invention with their ideas and arrangements . Fortunately there seem to be about a dozen (long) albums to plough through, I’ve been through them all but it will be a while before they become familiar enough that I know what’s coming next .I've tried a lot of their peers in psytrance and EDM and very much of it comes off as repetitive and monotonous in comparison..
I have got one Boards of Canada album (as you say not quite the same but good all the same) but sphongle are new to me, I will investigate further. I have been trying the likes of The Orb..boring etc. I do like some of Stereolab, some of the Nightmares on Wax stuff and for late night laid back stuff Sebastian Tellier is great.
many thanks for your suggestions.