Been to the FOS a few time, its great
+1 on Bockaaarck's advice
As other have said I would not bother with the grandstands, there is so much to see and you can get a good view from the standing areas.
The first time I want was the best, my sisters ex hubby was Murray Walkers bodyguard so not only did we get in for free, we had access ALL areas. Murray was a really nice bloke Had lunch with JB... well on the same table. And I bumped in to Barry Sheene ... literally "Ooops sorry mate".
The funniest was walking out of the drivers area with two bodyguards, and a few in the crowd muttering "who's he, is he a racing driver" :lol: