I would highly recommend staying at Alberto and Yao's lovely apartment. The flat itself is located in vibrant and interesting Shoreditch, where you can find a fantastic range of cafes, restaurants and shops. Shoreditch itself is also a great base for exploring all that London has to offer.
Alberto and Yao were incredibly welcoming, warm and friendly, and are both interesting, funny and well travelled. They really were a pleasure to get to know, and I would stay with them without hesitation next time I'm in London.