I'd like to toss in a bit of blasphemy here: I don't carry a signal mirror. I'm not oposed to carrying them, it's just a reflection of what I deem most important in MY situation and my climate.

Foul weather plays a large part in a lot of the troubles I try to take precautions against. Of course I could be in trouble in nice weather, but the situation will be A LOT easier to resolve then, even without a mirror.

I may actually get a mirror and toss it in my kit, just for good measures. But living where I live I don't judge it as so crucial as say, someone in Arizona.