Is this a good gaming PC configuration?

Hey, so I have been looking to get a new gaming PC for a while now. I seriously considered building my own, but that's not gonna happen. So now I need your advice on what to get. I was originally going to buy this, but after my mate bought it and said he had to get a refund because it didn't work, i'm not so keen on it.

http://www.amazon.co.uk/gp/product/B004KE2UW8/ref=gno_c...

Do let me know if I should take the risk with buying that one anyway, after all I won't lose anything if i'm refunded.

So I went onto cyberpower, which was always my second choice, and I have made this configuration.

http://www.cyberpowersystem.co.uk/saving/show.aspx?id=5...

1) Is that any good?
2) Could I get much better for that price, or is it worth the money if I want it built for me?
3) Would there be any way to slash some of the price off without making it terrible? (I am willing to spend that much but would rather pay less)

I know it doesn't come with an operating system, I will sort that out when I have it.

All help would be appreciated. Thanks a lot.