I stayed at the Renaissance a week ago on an overnight connection at Heathrow. My experience matches those of recent posters here. The hotel is dated. It's a huge layout, and I had an extremely long walk between my room and the lifts. Front desk staff probably took my "high floor, far from elevator" preference too seriously. Executive lounge spread in the evening was laughably poor. I went down to the bar instead and enjoyed a fine steak sandwich. Overall I felt the room wasn't worth what I paid for it, though nicer places like the Marriott were at least 50% more expensive so probably almost everything is overpriced to me right now.