Camping and Outdoors backpacking equipment...?

The Snow Peak Trek Series is a really nice cooking set up and there is a difference in volume between the 900 and 1400. These numbers indicate the volume of each pot in milliliters. 900 milliliters should be plenty of volume for you if you are planning on taking this trip by yourself. If you like to do a lot of cooking, then maybe the 1400ml pot would be a better option for you. On my solo trips I carry a .85 L pot (850ml) very similar to the Snow Peak series that you mentioned, accept without the fry pan lid, and it works great for me. The way I always judge a pot is whether or not I can cook 2 packets of Ramen at the same time in the one pot, and if I can do that then I can cook just about whatever I want in that size pot. As far as water purification goes I would recommend a chemical treatment like Aquamira (chlorine dioxide) because of its small package and lightweight, and because it sounds as if you plan on making your backcountry trips as side trips from your x-country backpack. I would not want to be carrying around a big heavy water filter all the time if I were only planning on being in the backcountry for some of my USA tour. I hope this helps.