Hi 20vmk2_dub,
As a general rule, I think most people tend to return to the camp site they used the year before. This must mean that when push comes to shove, they are all pretty good really.
Location is probably the biggest difference as it's a bit of a treck to the main stands for some, but then they are closer to some good trackside viewing. 6 and two threes.
MB tends to attract more hard core groups who set up their own village. (most of which are on this forum I undestand...

)
We started in KN but have found HA to be in a better position for what we wanted.
As long as it's one of the on-site camping sites, you can't really go wrong.