My partner and I have done it a few times. For the first couple of GPs in Cardiff it was fantastic. However, the last two times it felt a lot less exclusive. Everyone was crammed into the dining room and the quality of the food wasn't great. The smart gifts that you used to get in your goody bag such as the methanol club jackets have now been replaced with sponsors mouse mats and key rings. Now the price has risen to £350 it's just not value for money. You'd be better off buying good tickets and booking a table at a decent restaurant.
Having said all of that. The one thing that you will experience is walking out from the pits, down the tunnel the riders come out of to the side of the track. The first time I did that and saw and heard the crowd it really was a hair standing up on the back of my neck moment. You couldn't buy that.
