LHR - utter $hithole. Car parking bŁoody miles from the terminal, traffic jams on the inner airport roads. Scenic tours with a madman at the wheel of the transit bus, taking in the bowels of T1 to get to T2 - which is like a downmarket bus station. The whole place looks like a junkyard - and it's unbelievably expensive.
So nowadays I use BHX!