I finally got with the program and setup US accounts for iTunes, Netflix and XBox Live. I'm trialling UnoDNS currently to access Netflix but performance is terrible and I'm not sure where the issue lies. At first I thought it might be my WiFi seeing the Xbox and router are reasonably far away so I've just run a cable under the house directly from the router to the Xbox in the living room but the issues persist.
The program initially loads quickly from Netflix but without fail will re-buffer within a minute, sit at 25% for around 20 seconds, then either spit me out saying the Title is Unavailable, or it will start playing again, only to re-buffer again a minute later. Exactly what happened via WiFi.
I'm on Vodafone's Ultra Fast 130 plan, Cisco cable modem connected to the gigabit WAN port on a Linksys E4200 router. Xbox is connected to that directly now, also on a gigabit port.
UnoDNS suggested I try the OpenDNS test to see if Vodafone's transparent proxy is the issue but that test came back clean so at this stage I'm at a bit of a loss. If anyone has any suggestions I'll gladly take them.
Edit: I should add, I've only configured UnoDNS settings on the Xbox as that's the only device accessing Netflix...