I've got a pocket chainsaw too, though I've never really had to use it. I have it in the car emergency kit now for the same reason Junkyard does. We were on a roadtrip once and came upon a fallen tree on a remote road; if I had the saw then, we probably wouldn't have had to backtrack and waste time finding an alternate route.
I think for hiking/backpacking I'd rather go with a folding saw because you can saw with one hand and use your other to stabilize, or not use it at all if it's injured. But I don't really saw much with the activities I normally do, so I can't say for sure.
The nice thing about the pocket chainsaw, as pointed out, is the size. It's very compact. When I used to carry it in my pack, I ditched the plastic handles and added paracord loops to mine as well, you can just use stout sticks for improvised handles. :thumbup: It is relatively heavy though, definitely not an ultralight item.