Excellent service when it works, but so far, really unreliable and not necessarily NOTAM'd in time.
Coming round the zone from Biggin-Denham the other day, called Thames Radar who said 'Negative FIS, contact Farnborough Radar on...no, hang on, I've just been told thy're off the air, you have Flight Information Service'
I said 'Flight info thanks, I can't work out when Farnborough are available'
'You and me. both!' he said.
I've tried using the service when instructing. Great when transiting to and fro the training area, but when you're doing stalling & trying to talk to the student etc it just gets in the way. We do most of our upper air work north of Aylesbury, on the edge of their cover anyway. I usually call Halton there so I can find out what glider traffic might be about, difficult to spot visually and tends not to show up on Radar anyway.
TheOddOne