Which one Better for Biomedical Engineering: Carnegie Mellon or Imperial College London

Hi, I am an Undergraduate student offered admission to both Imperial College in London and Carnegie Mellon in Pittsburgh. What are your thoughts on which one I should go to? At CMU the biomedical engineering program is available only as a double major with a traditional engineering field, whereas at Imperial it is the sole degree. What school is more renowned for its biomedical engineering program? Additionally, what are the major differences in education between the UK and the US?