A wonderful flat with a wonderful view, tastefully chic, perfectly located within easy reach of London's big destinations and hidden gems. Annabelle was reliable, friendly, and flexible. I recommend this place without hesitation.
One note to Americans traveling in summer: on our trip, the weather was unusually hot (30C/85F); the western exposure of the flat's windows created a likewise unusually hot indoor temp in the evenings. This isn't a complaint at all, but just something to note for summer travelers made weak by air conditioning.
Last thing: while we spent our trip hopping throughout central London, we somehow ignored Pimlico itself until the eve of our departure. That was a missed opportunity—there are several cool shops and cafes, and we had an amazing dinner at Pimlico Tandoori. If you stay in the flat, reserve some time to explore the village.