al ferof is my pick at the minute. but sprinter sacre could blow them all out of the water - cant be sure of that though.
call me sceptical, but when i see betting spokespeople/marketing puppets claiming to have laid 250k in one morning, it reminds me of fat wilshire running around with his made-up betting slips for "fawwwwty five faaaaaaaznd paaands" during royal ascot or epsom.
plus, every time there is a well backed fave in a race that attracts bets from racing and non-racing followers - eg kauto when odds on for the gold cup etc - the bookies are always looking at a 'two million pound payout'.