There is only one airport hotel at Heathrow. All the others so labeled are liars. Our day in London was divided into unequal thirds. One part sleeping, one part city, and one part transportation. Our city section was the smallest of the three units, coming in at only six hours, including tube time.
The biggest and most unnecessary transportation time suck was to and from the hotel. Heathrow “airport” hotels are far from the airport and serviced by a third party shuttle service. That means that the bus that swings by Heathrow every half hour to pick you up is also picking up people for other hotels. (And since it’s a third party it is an extra fee. However the only other option is taxi which is even more money and a lot of the cab drivers refuse the fare to the hotels.) Then to head out on your adventure you need to wait for the next shuttle, return to the airport, and THEN take the tube downtown. (And that is why I recommend the Heathrow Express.)
So I mean it when I say: under no circumstances should you stay at an “airport” hotel at Heathrow. Never, ever, ever, ever, ever. Downtown would have been cheaper and easier and faster and better in absolutely every way. It was hard to keep in check my disappointment that this secret had stolen so much of our time (and an unnecessarily about of money. It even cost more than advertised and the drivers argued with us over the published price and the price they were charging.)
But on the plus side Heathrow Airport Terminal 5 had a lovely art installation celebrating neurodiversity. When I was feeling really down I went out of my way to walk under it again. Just for the pick me up. Art matters. (But so does honesty and proper labeling.)