My Gossamer Gear Mariposa has no back "padding." So I do use the 2 section Z-Lite on top of my fully deflated Prolite 3 Short as additional pack support. I put it on top so that the Z-Lite contacts my back. It feels great and provides additional air flow with it's dimpled design. Plus, it's super convenient to pull out any time I stop to rest - and just the right size for sitting or kneeling. Typicaly, I'll insert it into the footbox of my quilt at night so I don't lose it while I move around.
As for the Platypus Hoser, I just switched from a Big Zip, so I'll have to see how it goes. I did have a Big Zip leak around the hose attachment in the field but repaired it with seam grip and duct tape. Although it didn't fail along the zipper, I just wanted to go lighter and simpler. Plus, I can use a smaller silt filter when filling (Besides, Glen Van Peski showed me how to fill up a Platy using a zip lock bag when water sources are shallow so I'm anxious to try it).
On the subject of GPS, I went to REI to spend my divident check on a Geko 301 only to discover that they no longer carry it and apparently Garmin has stoped making it. So I begrudgingly bought the Foretrex 101 (albeit, quite a bit cheaper than the Geko 301 at $130). Well, I like the wrist mounted setup, especially with trekking poles. The 101 takes AAAs, so you can put lithiums in it. All in all, I'm happy with it.
As for my first aid kit, here's what's in it:
MAJOR WOUND SUPPLIES
2" X 75 " sterile stretch gauze bandage
compression bandage (ACE style with Velcro)
small role clear plastic medical tape (custom rolled)
2 doses of Percacet in small flip case
tincture of benzoin in mini dropper bottle
1 packet of Burn Jel
Moleskin (2 squares - use benzoin tincture to stick)
(Also duct tape stored around trekking pole)
MINOR WOUND SUPPLIES
2 antseptic towelettes
2 packets of triple antibiotic ointment
2 packets of Ivy Cleanse towelettes
2 Spenco Second Skin Self-Sealing Cut Closures
1 Band-Aid (medium)
1 Band-Aid (small)
5 Band-Aid Steri-style wound closures
1 Band-Aid Liquid Bandage applicator stick
Band-Aid Liquid Bandage in micro dropper bottle
Corta-Gel in mini dropper bottle
2 packets (2 pills each) of Benadryl
3 packets (2 pills each) of Imodium A-D
small folding scissors (key for Moleskin)
tick pulling tool
mini magnifying glass (for ticks)
2 safety pins (small & medium)
Now, I know I have a range of minor wound options (and I'm starting to notice the excess after typing them all out), but there's nothing like having the right tool for the job when the job is dealing with a medical situation.