What I think people need to realize is that the Combitube is not designed to replace the ETT. The Combitube is designed for non-ALS levels of EMS. In Wisconsin, which is the only state that I can really comment on) Combitubes are allowed all the way to the First REsponder level. Very simply, it provides a better airway and less chance of inflation of the stomache than an Oral Airway when using a BVM. The only time it is being used is during cardiac arrest.
I disagree with the statement that improper placement causes death. Ok, that part is true, but the chance of an improper placement is pretty low. The Dual-Lumen system allows for placement in the esophogus (primary), but also allows for placement in the trachea. I believe that Kendal says that it will work in 95% of all patients.
I agree that the Combitube does have some severe disadvantages, but I don't think that they override the advantage of providing some sort of advanced airway for the cardiac arrest patient in the BLS setting. Not to mention, there is no where near the risk of inexperienced or untrained personnel performing intubation. Not to mention, trauma to the oropharynx is the least of my concern during a cardiac arrest.