It turns out I can return it to Orange within 14 days if I hate it. So that's that sorted.
But if it turns out I do like it then what if I'm left with an unsupported device in 6 to 12 months? Either Microsoft, Nokia or Orange stiffing me. Ho hum. Proper First World Problem this is
Something else to keep in mind is Windows 8/Windows Phone 8. From what I can gather the Lumia should run it and with Windows 8 I see a bright future for the phone version.