OP: listen to me here: transferring is not worth it. midyear transfer won't happen, so you'll have to do it at the end of the year, which just creates a whole problem of matching the second semester subjects and then moving courses into a new cohort. it's really not worth it that much, given that you'll already be a third of the way through your degree. if you really,
really must try then good luck, but if I was in your situation I would stay in the BSc, try to excel on the GAMSAT and pick a major you enjoy anyway.
Dunno about how it is in 2nd and 3rd years, but 1st year biomed didn't seem to be any harder than 1st year science. I think people just like to complain, or think that their degree is harder than other's...
First year is easy, 2nd and 3rd years are a big difficulty increase
May i ask you why people do Biomed or why its competitive if science provides almost the same course.
1) Prestige
2) UoM's awesome advertising and marketing skills
That's all 
Since you have no experience of either course, you're missing out on
3) Biomedicine prepares you better for a medical degree