I booked had a successful BRG at Hilton Terminal 4 London Heathrow in May 2015. Hilton was showing £100.50 while Expedia.co.uk was £83.75. Within 24 hours my booking has been updated to include £30 off Expedia's price which was luckily as the rate was non-refundable. Just checked Hilton website and it's still showing the rooms at £100.