So...MAMS is a Master's degree program and the U South Carolina program is a certificate? Based on that, I presume MAMS would take longer. Also the Carolina program specifically mentions that it is for premedical students and that they offer MCAT prep. So that's a plus, but it looks like you already took the MCAT if you got into MAMS.
But, the MAMS's association with Boston Medical School could be a plus if you want to apply there later.
Really you should just call them and ask what percentage of their respective program's students apply to medical school and ask for the acceptance rates/if they provide them.