Very diplomatic of you Crab! What you say is largely true, but sadly there are occasions of air ambulance units trying to keep the stats up rather than admitting defeat and summoning a SAR aircraft. Perhaps this would happen less often if they didn't have to rely on donations from the public?
On a similar subject, here is an example of why close cooperation between SAR and ambulance control needs to be constantly pursued:
www.scotcourts.gov.uk/opinions/2010FAI29.html
It's a long and sad story, and the author is evidently unaware of the difference between an air ambulance and a rescue helicopter, but the point is that time was wasted summoning the SAR aircraft (see Part II Section 3 paras 29-38).