I really wanted to give this place 5 stars if not for Rob's positive attitude. He is a very nice host and will go out of his way to make you feel welcomed. There is a nice welcome booklet that gives you a breakdown of things to do in the area, and Rob is very responsive by text if needed. But while this place is very clean, the place is nowhere near 5 stars.
First and foremost - the location. I wasn't a huge fan of Elephant & Castle. I reject wholeheartedly that its the heart of London. I thought I was staying somewhere that I could walk out of my place and go hit a pub or tourist area. Definitely not the case. There is a mall next door to the building and its somewhat runs down. The whole area is like an up and coming part of London, but not a place I'd ever want to stay in again.
The unit is very nice, modern, simple, etc - everything you'd want - but there are a few shortcomings. It sleeps very hot. There is an AC, but it doesn't work well, so plan to be hot.
Overall, its a nice unit and definitely 4 stars, but not a 5 star Air BNB experience.