Does anyone have any experience of the azur540a (Amp) and 540c (CD Player)? I was going to go for the 640 series, but at £50 more a pop - its £100 saved, which to a 17 year old is quite a lot! Half way to the nice DAB tuner in the range. I am pretty sure I'm going to buy this set-up, but wondered if anyone had any feedback they could make which would influence my decision. Thank you :)