I'll take a less metrics-oriented perspective (though the previous points are fine). Many experts here can talk more about the MCAT and the publication count for a strong candidacy.
I would encourage you to consider why you want the extended path of MD/PhD education compared to a straight-up MD track or a PhD track (pending grant funding). There are some programs that offer extra time for student scholarship, so you shouldn't go "MSTP or bust" IMO.
Think about what your future would look like and how both degrees allows you to open doors to that career picture. Most MSTPs love the academic medicine life with the triple-threat of being a solid researcher, teacher, and administrator. You could be creative enough to be part of industry, but it seems like a long road. I ask about how candidates see themselves conducting "translational research" and why the deferred gratitude of the extra years (and salary differences) is worth that effort. Not everyone loves the grind of grant-writing or academic "service" that you will be expected to have if you stayed in academia.
Here are a couple of articles with slightly different perspectives about pursuing health professional+PhD tracks. Reflect on the similarities and the focus should you wind up deciding to do MD/PhD. But always consider your options in MD-only as well.
For pre-veterinary students with a keen interest in research, pursuing a combined DVM/PhD program can open a world of opportunities at the intersection of
www.studentdoctor.net
Do you want to deliver oral health care and dive deeper into the mechanisms that initiate and promote diseases of the orofacial complex? A combined
www.studentdoctor.net
