The 3 canned and 10 templated messages don't seem like enough for useful communication to someone back home. I'd want: Delayed, detouring, pick me up at new place and time, ... to really use these you'd need to pair it with a bluetooth keyboard, which doesn't tempt me. Still, it meets the basic use case of "I'm delayed but alive, do NOT call SAR" (and also, of course, the "SOS" use case, for which embedded GPS coordinates are great).
Pricing is confusing. $350ish for the hardware, plus choice of annual or monthly subscription fee (the monthly plan can be suspended for the off season), plus an additional "activation" fee when you actually use the device. (If I understand correctly, the activation fee covers use for a year.)
Looks like it would be very hard to use in a cold-weather emergency. But that's probably not a fair criticism, I don't know if any devices are designed for use with mittens on.
It doesn't tempt me much. My standing instruction for folks back home is "do not call SAR." Further communication with home would be just to reassure them with details, and this thing is hard to use for that. The SOS feature would be useful in a broken-leg, solo scenario. This looks more reliable than SPOT, the price isn't insane, and the form factor is not a barrier. Each time an improved device like this comes out, I have fewer excuses.