I have it on good authority that it doubles the salary.
Definitely worth taking into account.
To the OP, I had the same dilemma as you. I couldn't decide between Medicine and science. I could think of many ways in which medicine would be an advantage, but I am very much a scientist at heart and wanted to study science in detail. I was completely unable to decide, and got really panicked.
It wasn't until I approached the choice from a different perspective that I was able to decide. I started to simply consider whether I wanted to be a doctor, and ignore the pros and cons of any alternative. I did hospital work experience, which I liked, and GP work experience, which I loved, and quite a bit of reading. Eventually I could say that I did really want to be a doctor. After that, everything fell into place, because I knew there was only one possible degree course. I told myself to ignore the craving for basic science, because I now had a real desire to study medicine. (Although, I have to admit, I still get quite worried reading Saffie's posts, wondering if I made the right choice, and if medicine will bore me because it has so little science...hope not).
Anyway, that was how I settled on medicine. I just have to hope I'll enjoy it. If I hate it, I can always change course.
Most of all, don't stress about the decision! That was my mistake, and I worried myself silly. Make the best, most reasoned choice you can under the circumstances, and remember you can always change at a later stage. Oh, and take A-levels that keep your options open.
One more thing: don't worry that a science degree won't have enough work in! If you want broad, you can always choose a very general degree like biological sciences. UCL, Birmingham and Durham also have NatSci courses.