I would only talk about the survival stuff only if it is a natural part of your conversation. They will resist "proselytizing" if you go out of your way to talk about it. Things like, the new generator (good for hurricanes and ice storms), the extra food (good for hurricanes and ice storms), flashlights ( good for hurricanes and ice storms), and first aid supply upgrades (good for hurricanes and ice storms). But, if they love college basketball, football, or whatever and blab about it, that leaves the door open to your interests. Just make sure you have a natural, everyday, matter-of-fact tone about it.

Have fun!

Oh, and wear the helmet and flak jacket. crazy

My $.02
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"Its not a matter of being ready as it is being prepared" -- B. E. J. Taylor