Johnny, you can't just go on heresay to compare them!
Both are top events to do as a 1st event. Both excellently organised, both have their certain interest, whether you're a football fan, or F1 fan.
Both pretty easy to get parked up at (if you have designated parking at Reading).
Silverstone i think is a bit faster, it's flat but always a bit windy. Reading is only windy down the last 3mile section, but has a couple of hills.
Epic finish at Reading, but then not exactly a bad experience at Silverstone too.
To be honest I'd sack both off and do Wokingham, for pure speed 