I also ALWAYS carry at the very least a metal cup that fits over a Nalgene bottle. Yes, my kits ALWAYS carry fire starting supplies. All chemical purification methods have a wait time before the chemicals have had time to work against the impurities. If you have a pot and a fire, I would recommend boiling, after pre-filtering the water if you can.

The Aqua Pouch Plus just gives an option, and a backup, for a survival situation. Not everyone carries a metal cup or pot, and this kit fits very well in a pocket. Easy to carry and more likely to be with you when something bad happens.

I would also recommend a good filter pump or one of those gravity fed systems with a good filter. These are much more effective and quicker than a chemical method. They weigh more and take up more room, but if I am carrying a backpack, I have one. But I still have the Aqua pouch in my pocket.

I am prejudiced by my experiences, and I have been in some bad situations in the past. I have found that a reasonable redundancy in a critical system/need is a wise thing to have. Water is a critical need, and I have multiple methods for procurement and purification (boiling, filter, chemical). I do not recommend the Aqua Pouch as a primary method for water procurement and purification. It provides an additional option at little cost in money, space or weight.

I also carry redundancies in fire making, shelter and signaling. Knowledge combined with some new materials and devices allows for a light load in spite of redundancies. A minimum capability is kept on my body, my pack will carry more. One problem I have is that I am always with other people for whom I am responsible, so I carry more to ensure safety. While I do teach and prepare them for emergency situations, I am accustomed to relying on myself alone to ensure their safety.

This discussion of pros and cons of different methods is good, and can benefit anyone who reads these forums. That is how we learn.