This is a question that comes up periodically. There has only ever been one poster that I am aware of that has really visited this site that was in an osteopathic gas residency. I will see if I can find him with a search later today. So there is a relative lack of information about DO gas residencies here and most of what you will is simply opinion rather than hard facts.
What I can tell you with certainty is that the ABA (Amercian Board of Anesthesiology) board certification is the "gold standard" and for this reason alone I would encorage you to pursue an ACGME residency.
DO residencies are typically at smaller community hospitals. I do not know if this is true for the gas programs. Smaller hospital means less case complexity usually. So you may get a lot of "bread and butter" but may get farmed out somewhere else for a few rotations so that you can get your numbers. I get the feeling that a DO gas residency prepares you well from a practical perspective but the didactics are probably lacking somewhat due to the small class sizes. Allopathic programs have very structured didactics (which may or may not be good, depending on the program itself).
So if you know you want to practice in an area where there a lot of DO's w/osteopathic gas training already, it probably isn't a bad idea. HOWEVER, in many area of the country these programs are absolutely an unknown entity and you could have some serious trouble getting a job is some areas. One of the reasons I am glad I ended up where I did for my residency is that it is in the geographic are where I intend to reside. So there are grads from my program all over the state.
Finally, unforunately DO discrimination is alive and well today despite the claptrap and drivel that is propogated on some of the other forums here. I specifically know of two healthcare systems that DO NOT accept AOA training for ANY residency - they WILL NOT credential you. If you aren't credentialed you aren't working.
