If the budget can be stretched to £350-£450, I would recommend a Dell Latitude from the Dell business Outlet, I can't suggest any particular model or item because it's always changing by the minute, but you can score some really nice machines for the money if you keep an eye out. For example, I just found this;
Code:
Scratch and Dent
Latitude 3570
•Processor: Intel® Core™ i5-6200U (3M Cache, up to 2.80 GHz)
•Windows® 8.1 Pro
•8 GB DDR3 1600MHz Memory (1x8GB)
•1 TB SATA Hard Drive (5400 RPM)
•No Optical Device
•Intel HD Graphics
•NVIDIA GeForce GT920M 2B GDDR3
•Windows® 8.1 Pro (64Bit) English
•Dell Wireless 1802 Dual Band 802.11 2x2 AGN, 2.4GHz/5Ghz + Bluetooth 4.1
•No WWAN Card Included
•90W 3-Pin AC Adapter
•LCD Back Cover Non-Touch with Camera and Microphone
•Primary 6-cell 66W/HR Battery
•15.6 Inch FHD (1920x1080) Non-Touch Anti-Glare LCD
•Internal English Keyboard
For £420 inc vat.
Although not listed in the spec, the thing that sells it for me is the included 3-year warranty. Although my Dell Latitudes have generally been reliable, I've used the warranty service a number of times and I only have good things to say.