I used to be a PhD students at qmul (biomedical research). I highly dont recommend it.
They dont care about their students. If you have problem with your supervisor no one will help you. They all will be against you. Even if you have evidences proved that you are been treated with injustice by your supervisor.
From my experience and many people I met agreed with me that if you have a problem with your supervisor (which can easily happened) expect that the whole uni senior staff will be against you no matter how badly and injusticely you've been treated.
London is very expensive as well.
qmul is not highly ranked uni as well.