Opinions on surround setup?

[herr_brush]

OK after some discussion on here and lots of internet research I've decided on the following for a 5.1 setup:

Speakers:
KEF KHT2005.3 (£500)
http://whathifi.com/Review/KEF-KHT20053/

Amp:
Sony STR-DA2400ES (£370)
http://whathifi.com/Review/Sony-STR-DA2400ES/

This will have freeview/dvd/blueray connected to it and my PC.

For the PC, I'm currently using the on-board sound from an Asus P5Q-E mobo. Will upgrading to a separate card make a noticable difference to the sound quality? I mostly will use the pc for gaming but some movies and music as well. Also, does anyone have any experience/comments regarding the speaker and amp setup?

 

[herr_brush]

Thanks for that. I'll try to find a store where I can have a listen but I think the Kef's will be good enough quality and the price is quite good. As for the receiver there are a few online reviews that are all positive and it was the cheapest/best option i could find that included video upscaling.