Yep, I most certainly have. I am a teacher for an MCAT test company, and in a class of 25 students, I always have several skeptics. I try to be really nice, polite, and everything, just to educate them. I am very excited about my choice of medical schools, and when they see my enthusiasm, I think they take the extra moment to listen to what I have to say. I could be deluding myself, though. I think there are some out there that should NOT be in a DO school, b/c once they are there, they complain all the time about having to do/learn OMM. I would rather they just find an MD school.
I just try to show them the additional benefits of OMM as well as the whole body philosophy, which isn't all that different from many MD schools (or so our MD counterparts say--i don't know for sure since I'm not at an MD school).
This will be an attitude you may encounter now, but from what people say, once you ARE a doctor, no one cares if you are an MD or DO. The hardcore skeptics can find their way at an MD school.