It's quite pleasing and surprising to find an actual 17th century cottage, nicely converted with elegant up-to-date bathroom and a very agreeable lounge and dining area. I can't comment on the breakfast because my plane left too early. Pleasant host was helpful about places nearby to get evening meal, but did not get back to me to book a taxi for the next morning as he had said he would.
In general communication was not great. I was under the impression from the website that they could provide an airport transfer from Heathrow, but multiple calls emails ahead of time got no response. So I ended up paying 40 GBP for a 9 minute, 2.7 mile ride from Terminal 5.
In addition, I almost missed my morning flight when a scheduled taxi cancelled in the night. That's not the fault of Heathrow Cottages, but does show does illustrate the downside of booking a charming b&b a bit out of the way at the south end of the airport. It would have been cheaper for me to hire a car for the journey from Bury St Edmond on the morning of my flight.