-Why the tan version instead of the red one?
Thats what store I was buying it from had. No difference except for color.

-Have you by chance tried using the recommended dosage 1 liter dose for 1 liter of water? If so, did you ever find insufficient chlorine with a test strip?
Never did find insufficient amount. BUT it doesn't mean it can't happen. I was going away for 4 weeks and unit comes with 50 test strips (additionals are $15 w/ salt). Manual says you should test water after adding the solution and ten min after. So in my setup that meant 25 liters which was about 5 day supply. Overtreating was there to skip the PH test.

-What was your source of water? Why were you "Mioxing" it?
Streams, water taps, rivers anything that was up from the settlements and didn't look like yak pee.

-With the four 1-liter bottles, did you treat each one with separate doses from the Miox?
Yes. Each 1 liter bottle got 2 litter treatment.

-Do you think you'd have been have been better off treating one 4-liter Platypus bag, letting it work for the recommended time, and then pouring that into clean 1-liter bottles? I'm wondering if that would have been easier.
Great solution but than I'm out of water for 4 hours if I treat everything at the same time. If I treat it as I go than I have water always available. In your solutiuon you can treat 4 liters pour them into the bottles and than refil the bag and treat it. So next time you just distrubute the bag and keep toping it off. Great idea if weight was not an issue.

-From what I've read, the 1 cc syringe will exactly fill up the Miox completely, Right? Using the syringe is a great tip!!
To be anal about it it takes app 1.3 cc. Sometimes a bit more if I just added a fresh salt and they needed to absorb water.

-How long did you let the bottles sit before using? My plan is to let it sit for at least 30 minutes and longer if convenient (manual says Cryptosporidium needs 4 hours).
Most of the time I had 2 liters of treated water and 2 liters of untreated. Few times I was really short on aqua so I drank it after 30 min but that was a rare case. Most of the time my supply of treated water lasted me about 4 hours. But I drank water after 30 min treatment and I'm perfectly fine.