We stayed at 100 Queensgate for 13 nights from late September through the first week in October. The hotel was nicely situated in South Kensington near the Natural History Museum where I was working. The staff was good-natured and helpful. Excluding the bathroom, our small room was about 9 by 13 feet in size with a Queen size bed with small tables at the corner, a small closet (2 by 2-1/2 feet with 10 hangers), a side table (1-1/2 by 5-1/2 feet) with a small (5/6 cubic feet) refrigerator and coffee and tea makers. A small alcove (3 by 4-1/2 ft) had a chair and a small (18 in diameter) table. The bathroom with shower was especially nice. A lot of smallness.
For a long stay, a major drawback was lack of storage space. The bedside tables each had a single small 14-by-14-by-7-inch drawer (about 4/5 cubic feet), so that, with only 5 clothes hangers apiece, we had to live out of our suitcases. The hotel restaurant was very expensive (£57 per person per day for a buffet breakfast, £46 per person for afternoon tea). Room service meals were less expensive, but sometimes without salt and pepper and breakfast toast came without butter. Cups provided for making tea were too tall to fit in the coffee maker, so I had to buy a £5 mug at a local shop to make coffee. The hotel is definitely not designed for long stays and the small room with two small chairs encouraged us to be out and about. Our cost was just under $5,000 for the 13-night stay, not really a bargain. Location was best.