I started a undergrad MBiochem, at Jesus College, Oxford, although I didn't complete. My opinion of Oxford, from the time I was there, is that it has great facilities, and certainly has academics who are a the top of their game. Whether it's any better than other universities, especially the Russell group unis, is debateable. Certainly in sciences there seems to be little difference if any, with the "Oxbridge is better" statement being a myth perpetuated by those who have Oxbridge degrees. The place can be very stuffy, and it certainly isn't like living in the real world - I much preferred my time in Sheffield to my time in Oxford and, unless I found a superb, out-of-this-world project with a brilliant supervisor, I wouldn't touch Oxbridge again with a bargepole.