Alicia, I also chose the AquaBrick, which is made by Sagan Life. I like it for the same reasons you mentioned: it is not too heavy for me to carry, has two conveniently placed handles, and can be stacked. Also, the rectangular shape saves storage space. A Sagan Representative told me they can be stacked 5-6 high, but they shouldn’t be placed directly on cement. I’ve had mine stacked three high for over a year, and they have not leaked. It might be of interest to note that I initially ordered 10, and of those, two of them leaked around the lids right away. I contacted Sagan Life, and they quickly sent me two replacements, at no charge. Customer service at Sagan Life was great. They told me to keep the defective containers and use them to store dry goods. I now store rice in them.
Alicia, I found the YouTube video to be very helpful! Like you, I have been looking for smaller containers, because 5 gallons is just too heavy for me to carry. I wish other containers in the 3 to 3.5 gallon size range had been included in the review above; I didn’t see anything mentioned besides the WaterBrick, which the YouTube video shows to be clearly inferior to the AquaBrick. I’m going to try the AquaBrick!