If one doesn't want a tucker terra, the mat-tracks certainly work for those who have a use for them. When you think of the difference in contact patch of a tire vs. a track, it's gotta be at least 5 if not 10 times as much area, hence much less weight compacting the snow.
Haven't heard of any reliability probems, I know they use them on the slope and hence they can handle the cold. The only real issue is cost and loss of fuel economy.
And yes, if you get stuck far from help, you'd be fucked!