I bought and installed a JVC AVX840 a few months ago, think there's a newer model out now though and it's great! Touchscreen, iPod/iPhone connectivity, camera input and all the other usual gubbins. Think I paid £250 as they price matched the wrong model so I saved about £100.
The new model is this one I think - http://www.caraudiocentre.co.uk/product_m-jvc-kw-av70bt_p-27469.htm
Read reviews though as I know the model below mine had issues which mine avoided.