Here is my story in case you care. I applied to medical school during my senior year of undergrad with a 3.60 Cum, 3.50 science and 511 MCAT. Not really great stats, but not god awful either. I received 1 MD interview and then wound up getting immediately rejected. I then wound up doing an SMP thw following year where I got a 3.80 GPA. In the end I wound up with 8 interviews (7 MD and 1 DO) during my second cycle while at the SMP. I wound up getting into that DO school immediately and wound up sitting on 7 MD waitlists until May. I then got off the waitlist for my last choice MD school in May and committed to there. Just when I thought I would settle, my top choice MD school (where I currently attend) gave me an offer in mid-June. The point to this story is that an SMP can help you if you go and do well. Also, the other take away is that you can do everything right and still barely make it in to med school.
Best of luck on your journey!