Trying reading the osteopathic forums on this point. There is a large discrepancy in terms of clinical training between DO schools and MD schools. In MD schools, the vast majority of training is done in teaching hospitals with residencies. This is not true for a lot of DO schools. There are DO students who go the vast majority of their training mainly under only the preceptor (one attending). Sure almost all DO schools will have students who rotate with residents maybe 1 or 2 rotations. However, compare that to MD schools where 7-10+ rotations are done under residencies. The older schools such as DMU, KCU, NOVA etc. are exception where the majority of training is done under residency programs.
Program directors of ACGME residencies see this discrepancy with DO students, and will thusly prefer an MD student over a DO one. It is not something you can simply make up during your audition rotations and sub-i's. During this time, you are trying to impress programs with what you know from your core rotations. If you are struggling with patient notes and presentations, you will not be leaving a good impression with the programs you are trying to match into. This is why it is important that training under residencies are done during your core rotations. (it doesn't mean you don't get anything from preceptor based rotations, but you want to have an understand of how to function as a resident)
Having those programs close to the school also mean there is a less likely hood of a BCOM student being dropped from a rotation and even from BCOM students being dropped altogether. For instance, schools such as KYCOM, LMU, VCOM had sites in Alabama. As soon as ACOM came up, these students were pushed out by the local school. My MD school did the same thing to ATSU-SOMA students. Locality of these clinical partners plays a huge roll in preventing BCOM students from having dropped rotations, especially with schools expanding out.
It doesn't mean that one should not be cautious of entering a new program. There will be pitfalls definitely. However, one should truly understand the opportunities one is getting from a school. For instance, look at MUCOM. People on this forum hounded this school from the first class. The reason is because of the strong clinical affiliations it has set up in Indianapolis, as well as the state of Indiana. I have read the comments by third years at MUCOM and all of which were extremely good. This doesn't take away from your point in being cautious of a new schools, but you really need to understand what having these residency programs and clinical partners really mean. If one is accepted to a school with an already strong history of matching and clinical affiliations such as ATSU-KCOM, then obviously one should pick the established schools (because they have a track record). However, there are schools that have a horrible track record, and if accepted into that school and BCOM (then one should give consideration to BCOM or a new school with potential).
I do agree with your point in being careful. However, one should not underestimate or overlook aspects of a new school either.