We all have different requirements for equipment. If something doesn't meet your expectations, you're under no obligation to use it. Very simple.
SPoT's 911 function seems like it should be pretty reliable as long as everyone understands it's not going to be instantaneous (i.e., the first 911 message may not go through, or even the 5th one). In today's culture, at least in the USA, everything is expected to happen 'right now', but SPoT may not provide that level of performance. For that, you'll need an Iridium satellite phone and the cognitive capacity to operate it. Most of us can't afford the phone, and, at the worst of times, may not be physically able to operate it. (PLBs, depending on their configuration, your latitude and satellite tracks, may also take a significant amount to time to calculate and report your position.)
As for the belt clip, I agree that its inclusion could be misleading becuase it orients the antennas incorrectly during use. Perhaps the belt clip is meant to provide a convenient way to carry the device between uses -- it's rather big to put in a pocket, right? As an alternative, I'd suggest big letters molded into the top of the unit that say 'This side up during use' and, rather than a belt clip, provide a pouch with a belt clip (implying that it should be removed from the pouch during use). An alternative that would require some retooling would be to have the unit look more like a golf tee or inverted L, with the antenna molded into the top so that it's oriented more correctly when clipped to a belt.
'00 Duke II
So many toads; so little rhyme