In reply to Jaymoe:
There are no "bad" harnesses - they all have to pass the same standards.
What you get needs to do 2 things - firstly fit you and secondly match the type of climbing you'll be doing.
Do try several on and see what's comfortable - most shops will have a rope so you can sit in them. The main bit to check is that the belay loop at the front isn't under tension and pulling the waist belt down when you're standing up normally.
If you're planning on just doing walls, then there's not much point getting something with lots of gear loops - if you're planning on using it for mountaineering, then padding is less important. The main thing I look for in a harness is twin buckles at the front/floating belay loop, so you can centralise the belay loop and the padding round your back ends up where it should be.
Beyond that, £65 will get you a good, all-round harness, so buy the one you like the look of.