Not for nothing, but the OP's thread title indicates that the BiPAP would need to be "EMS friendly", which to me screams watered down.
Now, there isn't a whole lot of critical thinking that goes along with understanding IPAP, EPAP, airway pressures, and the like, but it sounds as if a watered down BiPAP is useless without a bit more education of the advanced airway variety. Again, hardly a dig at anyone, but Bi-level airway pressures and their mechanics isn't something taught in most (basic) paramedic schools.
Should, or could it be? Absolutely, but just because you want some more intermediate (by the way, again, please share with us your reasoning and rationale for wanting such a device) airway pressure device for 5 minutes doesn't mean the cost allocations, let alone medical justifications are or would be warranted.
So, again, why would any standard ALS service need BiPAP vs. CPAP? If anything maybe you could justify purchasing ventilators for the entire department, upping the departments airway knowledge, take on vent-dependent IFT's, and recoup some money that way. Then you'd also have a machine capable of delivering BiPAP.