True, but terrain limitations apply the same to the systems it's competing with. I do agree it's stricter about pointing, but the manual on my inReach advises

True, but terrain limitations apply the same to the systems it's competing with. I do agree it's stricter about pointing, but the manual on my inReach advises that it be in a vertical position for maximum reliability--people typically hang such devices from their packs to provide vertical orientation and minimum obstruction. For a lightweight implementation of a satellite rescue system this sounds very good.