I really liked Duxford, great location, nice site with good hotels, pubs and every other amenity within easy access to every mode of transportation and really in keeping with the way that helicopter people do business.
I think having this event in a neutral location on a helicopter friendly airfield is the only way for it to really succeed, as it is quite unique and escapes all the other regulatory nonsense the UK is quite famous for.
I hated the Excel set-up, it was pretending to be something that it really isn't and is not a convenient location in my opinion. I'm not sure that there aren't other sites that would welcome this event, including Farnborough, or other places with some character and interesting features.
If be all for Duxford, again.