I love my Spot Sat Messenger and didn't mention your PLB because there was nothing negative to say about it
I know you mentioned the 5gal of water but there are many reasons to carry at least a few liters (in seperate 1 L bottles) in your ditch bag:
vehicle roll over destroys your 5gal
vehicle fire means grabs your bag and get out
vehicle on an off camber side slop and tipping over the edge...again grab your bag and go
tainted or suspect primary water
you live in NM and travel the desert southwest, as another person mentioned you can go 3 weeks without food but only 3 days without water (less in summer)
I know you are basing this on a 3 day senario, however it is important to look over real world events and how long the average "lost" person is out there. If you have a beacon/signal device and can let help know to come you are looking at under 24hrs, if something happens to your beacon you are looking at 3 days just to get started looking for you....I plan my stuff around the 3-5 day mark. And since I usually have my son with me then factor x2
As Flounder mentioned, it is important to look over your gear.Even more important is to test it. I have done winter testing in the high desert
http://www.expeditionportal.com/for...rgency-gear-testing-Winter-Edition?highlight=
I will try to get the pics fixed
and I have done summer testing in the desert (really need to post that) and I can tell you there is no better way to enjoy a solo trip than to make it a training adventure.
www.equippedtosurvive.org is a forum with real world, high quality people who actually use/test gear and aren't a bunch of end of the world nuts