Andy for proper lighting look at a HID conversion Kit. They getting cheaper now and the kits are getting better - you will never want to go back to halogen after using a set of these. www.hids4u.co.uk is where I got mine for both the saph and the mondeo. The kits are 90% reversable i.e. no cutting of wires needed to fit, and so long as you can find an existing hole to mount the balasts too there's no drilling either. The only thing you might need to do is cut a small hole on the back cover of the headlights to allow the loom to feed through - (couple of quid from the breakers for some spare ones to cut up?)

However, if you just wanna stick with halogen based ones, have a look at the Ring sportz blue bulbs. They are not as chavy as they sound and are by far the best halogen bulbs I've ever used.