Thought I'd give my thoughts on the new F56 HK system, compared to the old one. First of all, in my experience it always takes a good few hours of listening for the sound to develop in any new system. For the old HK I though it was rubbish at first, then it really improved and became pretty impressive (especially compared to the MINI Loudspeaker System I'd had before). The new one again disappointed at first, but now after a week it's really coming on. Compared to the old one, it lacks some outright volume, but the sound is warmer and more involving - I'm hearing details now I'd not noticed before - and the sound stage is a lot better - you feel you're sitting right inside the music now. At first I thought the bass speakers (which are under the front seats) weren't working, but they have become gradually louder and I've realised they're very deep and quite subtle. If you play something electronic with a heavy bass and put your hand under the seat you can feel a rhythmic breeze as the air pumps up and down! I found the old HK was best suited for electronic music (stuff like Jon Hopkins, Fourtet...) and rock (from classic Pink Floyd, Led Zep up to post rock stuff like Mogwai, Isis) but the new one is good enough for even real thrashy death metal (brings out layers you couldn't hear before) and maybe even classical as well with its really wide dynamic range (helped also by the fact that the petrol F56 I have now is much quiter inside than the R56 Dooper). So overall it's definitely a higher quality system - sounds more like a proper hifi. Can't wait to get back in the car now....