I wonder if there have been false distress signals in that
area ? That or adverse weather would be the only reasons for not calling in a SAR efford that I can think of.

I know with ELT's we have had so many false ones that unless there is a missing aircraft we just run a three person DF team to find it and shut it down.

As for thr GPS that's what extra batteries are for, come on how much space/weight for two to four AA batteries.

If I was going into the back country I would spend the 450.00 on a PLB with out a doubt.