Great decision to not be in London.
Both The Symphony Hall and Manchester's Bridgewater Hall are fantstic venues that would appear to fit the bill perfectly for what obviously would be a very special night!
Didn't Steve H and C.R. sell out both their shows at The Bridgewater Hall in 2005 and 2008?..so on that basis I'd have gone for Manchester! I know a one off like this would attract fans from all over the world,but I believe and it's only a belief that tickets would move a little faster with a gig a little further North!!and I'm also completely biased!!!!
Still, wherever it is, It HAS to be filmed.