OKAY..... (I work as an EMT, but also have fire experience and experience as a dispatcher) having read over the entire discussion, here is what I can deduce:
1.) EMS is relatively new in comparison with FD and LE services and as such is still very much "in the works" and a really streamlined way of providing a nationally standardized EMS response is far from complete.
2.) Due to the great lengths that the FD has gone to in regards to fire prevention, the number and severity of fires that are being responded to are greatly diminished and as such, fire needs a way to not only justify it's existence (and size) but also a way to generate additional revenue. EMS seems to be a great way for this, especially when hard facts are laid out: in the majority of regions nation-wide, medical calls comprise nearly 80% of an average FD's total runs.
3.) As some have mentioned previously in this forum, third service EMS is unfortunately very often used as a stepping stone for aspiring EMTs and medics to move on to bigger and better (paying) jobs in fire. Often, many in the biz move on to fire not so much because they don't like the EMS side of it, but because TSEMS doesn't pay nearly as well as a fire job and you really can't beat FD benefits.
4.) EMTs and Paramedics working for both TSEMS and FBEMS have the same level of training and have to pass the same national registry exam, so in both arenas the personnel responding are equally skilled and both systems find it possible to meet their mandated response times, so the whole argument about a faster response is moot (to those who doubt, talk to FFs in areas where the FD acts as first responder to a TSEMS company and ask them how often they are able to initiate ALS care before an ambulance shows up [not often] and then ask if that impacts the difficulty in keeping up their medic cert. Besides, as we all know, seconds don't really count but for maybe 1% of the calls, probably less. See what I'm driving at?)
These points are why FBEMS is gaining in popularity.... BUT DO THESE THINGS MAKE EITHER FBEMS OR TSEMS SUPERIOR OVER THE OTHER?
The answer: hardly.
In some regions FBEMS works great, in others, TSEMS seems to be best, but from the perspective of someone who has seen both in action, a third solution that I have yet to see suggested appears to be better than either. While there are pros and cons with both systems, what we really need is for EMS to move away from privatized companies and to be run by county/regional/city/state governmental systems and be run more like a fire dept, not dependent on how much money can be gleaned from medicare or restricted by a FD that views EMS as secondary to fire. AHHHHH!!!!! I KNOW!!! Scary, huh?
The problem is that TSEMS are run by private companies who are, to be honest, out to make a buck. I know, I know, hardly a new idea and not fair to all those "virtuous and honest" private EMS companies out there. But in the process of increasing profit margins, the employees and sometimes even the patients suffer for it. So why not make EMS a FD-like entity, something funded by our tax dollars (and what medicare begrudgingly pays out)?
It's true that sending an engine out to every sprained ankle is a waste of money, just as it is true that it is better to have all the necessary resources on hand rather than having to call for them later, so why not have both fire and EMS run by the same region, although separately, and use the dispatching protocols that are already in place in many areas implemented so that EMS can be dispatched and have fire dispatched as well when appropriate or expedient?
Just a thought.