I don't feel comfortable with the notion of a sequestered survival pack sitting unopened, all sealed up ready for the emergency. When I have been in a tight, critical situation, I have been very happy and comforted to be using familiar gear that I know from experience to be dependable. Now one doesn't use a signal mirror routinely, so that is something to play with beforehand, but the items you carry should be well used with their capabilities, advantages, and limitations clear to you.

When I light a stove or a fire, I like to be using techniques and tools that are familiar, as are the backups.

Even when activation of a PLB is warranted, do every thing in your power to deal with the situation. Outside assistance is never guaranteed..