#1. using amazon for purchase is contributing to anti-American businesses. Choose your loyality...
ebay has the same products.
#2. Hands down - Berkey filter. It is the best.
There are "jerry can" filters that use the Berky filter and the jerry can is more robust than the "travel" can of the Berkey. The Berky travel can is not meant for travel, it is just smaller so easier to carry around, but in no way set up for travel, you have to secure it for travel somehow.
If I had a do-over I would use a jerry can with Berky filters.
The store water is always contaminated and sometimes just carbon filtered (for taste) tap water.
Those other filters will not filter as good as a Berky.
Lots of toxins in American tap water.