I find that there is very little of interest/variety in the last decade or so at Farnborough, and would not pay the entry fee.
My last visit was 4 or 6 years ago and I parked up my motorbike at the western end (can't now as said above) and watched from the extended centreline up the small hill for about 45 minutes and saw all I wanted to.
Bit of a borefest imho.