Well I unlocked my bootloader last night, didn't end up putting any ROMs on it but had to start again with my Apps everything was working perfectly when I went to download everything (This is in Sale, about 5 miles from where I work). I even managed some Battle Field 3 online gaming via personal hotspot on my PC.
It was only late on last night I starting having an issue.. was it an app I installed I wonder? I will experiment further.
Shame its networked locked, was going to led it to my friend to try with his Vodfone sim to see how he gets on with it.