I’ve heard the GMAT or whatever it’s called it extremely challenging. There are pros and cons to taking a gap year, I personally took one and have no regrets. I got myself a full time job, saved lots of money and gained lots of real world experience. Obviously I’m going to be biased to taking a gap year. Doing another degree may make you realise you don’t want to do medicine in the first place. It’s a tricky choice either way!