Pros and cons of medicine with a foundation year?

Probably have to clarify more what you mean, as all UK trained medics have to do 2 foundation years and graduates from abroad who have full registration still have to complete the second foundation year unless they've worked in their own country to a higher level before. So effectively all medics do a foundation year. Unless you mean medicine the undergraduate course with an undergraduate foundation year for those who've not got the right A Levels/equivalent. I hope you see the confusion.