Nintendo_Fan:There's no point in buying that system, because the Tannoy fx5.1 isn't good enough to show the Sony's true capability, which would be better with £600 speaker packages.
I don't understand how you can say there is no point in buying this system. Yup, okay, a more expensive speaker package would sound better with the Sony but it's hardly pointless. I use an Onkyo 905 with the B&W 685 setup - ideally I could run a much more expensive speaker package with that amp, but it still sounds fantastic with the B&Ws.
My advice would be to go and listen to the system and then decide if it's pointless or not. The Sony 820 amp is a good bet as it will be future proof since it can accept and decode all the main new HD audio formats.