Time went bust once not sure I trust them that much to be honest. What do you want the laptop for? Is it for gaming or just general home use. Do you plan to do things like video editing or otherwise on it? Knowing this we can help more. Avoid laptops with intergrated graphics as at this price you can afford to get one with a seperate one. Aim for at least an ATI X300 card or the equivalent GeForce.
Acer do a nice line up of sub £800 notebooks. Core 2 processors. Good mid line graphics 120gb hard drive 2gb of ram and a 15.4 inch wide screen all for just shy of £800.