Hi, I am considering the options for the surround speakers in a 5.1 setup. I am going to use Artcoustic 75-55s for the fronts and their DF-multi for the centre. So the question is about subtle rears: Does anyone have first hand experience of in ceiling rears? I am being led towards something for around £800 like a speaker from Triad. Also has anyone compared in ceiling with on wall speakers as the alternative is to use the Artcoustic Diablos on the wall. This leads to the final part of the question which is side wall or rear wall. The main seating will be centered up against the rear wall. If it matters room dimensions are roughly 18ft wide and 12ft deep. Thanks, Chris.