Sorted. I decided to call in Phones4u, told them I was eager to get a K810i, they told me I might be unlucky as they're now rare. They could get me a previous model, k800i which is very much the same. I asked why they brought out the K810 if it wasn't much improved and was told SE held back because they new they'd be bringing out the K850i.

I told them that Vodaphone offered me this, and would charge me Ł29 for it. Phones4u said I could have it free and they would simply extend my contract.

My concern about the sensor keypads, was as Alec says, controlled by one locking key. So I've got this as yet unpacked phone and hopefully it will be fine.