Hey Moe!
As a controller at the North Sea's 'Offshore ATC Centre' a.k.a. Aberdeen I can tell you that the services we provide are of a good standard. Don't quote me on these figures, but in our 86,000 sq.miles of airspace, radar must cover around 70% of it (not bad considering most of the installations are 100-160nm from the beach) and RTF coverage at the same level must be in the order of 95%. Like I said those figures are off the top of my head - but won't be too wide of the mark.
The duration and type of service provided varies, with some sectors manned from 0630-2100 with some services available outside of those times. Radar Advisory Service (modified for the peculiarities of the task) is the normal radar service with an Enhanced Flight Information Service generally available outside of radar cover.
I would like to think most crews that Aberdeen handle are happy with the service we provide (if not I'm always happy to take comments on board) - sometimes our procedures and equipment aren't the best they can be, but we do work very hard to constantly improve our levels of service and safety to the crews engaged in a difficult operation.
At least icing won't be a problem in the Gulf - we're just at the beginning of that fun time of year!