This is a question to medical students in particular. The question is self explanatory. I am a year 12 student applying in October to Medicine- I'm pretty set on applying, though still open-minded on where to apply. I'm a northerner (from just outside Liverpool) so I'm quite keen on being in a similar style of city where the people are friendly and where there are lots of them. What are your universities like? (course structure, city etc).
You can get the information on both of what you're looking for by simply requesting/viewing the prospectuses of medical schools. They will give you information on the course structure, year group + uni size, cost of living and attractions in their respective/surrounding towns and cities etc.
This can all be seen online too and perhaps once you've done some legwork and narrowed down your choices and have more specific questions (which can't easily be looked up) you can ask them on here and get responses.
The TSR Medicine wiki also is riddled with information about course structure, university course pros/cons and there are TSR wiki pages generally about universities and their cities themselves. Don't expect to be spoonfed
Though if you have any specific questions about UCL or London, feel free to ask me - though I do expect you to read through the UCL medicine admissions website first as lots of info is covered on there about the course structure and requirements.