This in theory is great but from my experience with the SPOT the tracking feature is VERY unreliable. I've always left exact trail head locations and intended itinerary behind before a trip and SPOT hasn't really added much to that at all. On our last trip we walked along a river the entire time which meant pretty thin canopy and yet the SPOT still failed miserably at tracking us. We didn't have any tracks marked and on several miles of trails that doesn't exactly speed up a rescue effort much more than leaving a plan with someone. I personally think its a poor excuse for a tracking system, luckily I haven't had to test the rescue feature!