Dobbo
Yes its great - especially when the Corvettes accelerate into the nether in the direction of Indianapolis. I can guarantee that you will not get a wink of sleep.
I camp off circuit, but always park near Mulsanne village / bars and walk down to the track via the industrial estate ( 10 mins ).
The downside is when it rains - it gets very waterlogged so avoid the depressions when setting up site. However the regular guys can always throw you a blow up doll or two from their flagpoles if you are at risk of drowning.
The navette bus is a good 10 mins trek through the woods from Mulsanne corner, I fought the queues without any bother. Check out the 'It happened to me section' also. I discovered the free bus a 2 - 3 of years ago, and would never drive to the top of the circuit if I could help it. I use it to go from Mulsanne, upto the main gate / circuit to buy my t-shirts and have some champers, then hop onto the bus for a spell at Arnage before going back to Mulsanne for Saturday evening snap.
Regards
BryanC