I got a packalarm last year, love it. Have used it a few times and it's never been set off by wind or branches. Slept in a tent in bear country for years without one but it was only when my boy started coming with me that I really ever got concerned about bears at all. Still not really "concerned" but it is an extra bit of peace of mind at night. Not a substitute for keeping a clean camp and being smart with your food but it's a worthwhile little piece of kit to have.