Hey,
I am a first year at a DO school. I am here b/c I couldn't get into an allo school.
However, now that I am here, I can tell you that I am getting a comprehensive medical education (biochem, anatomy....) plus OMM. The way OMM is useful is:
1) in seeing how a LIVE Human being's muscles, bones, ligaments, organs, etc. work together to maintain health. Whereas if you only learn anatomy, you are only learning structures on a DEAD person. What is actually interesting is that anatomy and OMM complement each other very well.
2) Once a week we have OMM lab. So you end up touching people every week. You have to practice outside of class, so more touching of people. So you become comfortable having your hands on another human being. This, I believe, will be an asset during rotations, residency and beyond. Whether you routinely use OMM or not, you will be comfortable touching (palpating, diagnosing etc...).
3) In regards to residency placement, I do not have the appropriate data. But from what I hear on SDN, it is easier to get a more competitive residency after an allopathic med school. But I don't believe in statistics with regards to myself. I believe in myself, my personality, my drive and believe that I can do anything I choose to.... but that is just me. Don't mean to sound cocky; just being sincer.