Hi! I'll attempt to answer your questions. I've just graduated, started in 2010 and did the foundation year.
1) good A-level predictions is advantageous, I cannot see how that would work to your disadvantage. However since you are study science A-levels you might only be eligible to apply straight into the first year.
2) only Leeds accept application into Medicine after completion of year 1. However it is not unheard of to hear someone has transferred to another course (not medicine in the UK) at another university. It is also not unheard of hearing students studying medicine at universities outside of the UK after the completion of year 1.
3) best option is to finish the course
4) I have not heard of needing to take the BMAT/UKCAT during the selection/transfer process. It is usually after the transfer is complete that you might be asked to take the test and that's for data collection purposes.
5) it is very dependent on the intake year, it cannot be predicted. Many people get the 60% however that is the criteria to make the application. However it is not unheard of for Leeds to set another academic baseline e.g. 65% to be called for interview.
6) I started in 2010 in foundation with an intake of approximately 60 ish students. Year 1 there was around 100 of us, though I know the intake is steadily increasing to around 120 give or take. However Leeds reserves 20 places for transfer for both foundation year into year 1 and year 1 into year 2.
7) Usually academic performance prior to Clin Sci is not looked at, however if your grades are good it is advantageous. Yeah work experience and extra curricular activities play a very pivotal role in the application, as Leeds has a criteria they score outside of academics such as cultural awareness and your insight into medicine etc
8) I'm sorry I don't know
9) based on experience before hand preparation is not a necessity and does not guarantee success. The course surpass the detail learned in a-level both in foundation year and year 1. Staying on top of the work and not leaving anything last minute does play a big part on getting the grades in the majority of cases.
From my 4 year experience, clin sci is no walk in the park its a very intensive course that is very demanding, and what you put in is usually what is reflected in your grades. It prepares you in every way for a career into medicine and any other healthcare profession and is very respected by other medical schools outside of Leeds.
I did try to transfer to leeds in foundation year and year 1 and narrowly missed out. I did not apply to GEM and instead i'm going to business school. I know many course mates going to start medicine in September and though the clin sci experience has been questionable at times doing this course was the best decision. It beats having a gap year with no guarantee of the future and there is no harm earning a degree in the process.
Hope it answered your questions