You can get the Phenom II X4 955BE for under £200 too:
http://www.scan.co.uk/Product.aspx?WebProductId=1003114
This is very competitive with the Q9550 and is the fastest desktop processor AMD make.
Some reviews of the Phenom II X4 955BE:
http://techreport.com/articles.x/16796
http://www.guru3d.com/article/amd-ph...r-review-test/
The Phenom II X3 720 is also very good value for money too!!
Here is an overclocking review:
http://www.bit-tech.net/hardware/cpu...ii-x3-720-be/1
Remember to get a decent PSU too!!