I occasionally travel for amusement only on HSTs to Plymouth and back and use RTT to choose a day when 5E63 (ecs from Laira) is activated so that I return on a different set to the one on the outward (sad, I know) . It surprises me that the set off depot often has a number of defects - for instance, on 16th August I returned on such a set (with power cars 43007/184 freshly re-vinyled) and the 45xxx coach had poor or no air-con and bad wheel flats, and the lavatory in the adjacent 1st ran out of water before Taunton. Some of the vestibule doors either stayed, or wouldn't, open, but this seems to be an insoluble problem not confined to Laira..