I was a one week supply backer and last week I received my first shipment. My personal use for Soylent is as a Breakfast replacement. I will wait a few more days to post my initial reactions to the product.
Based on my usage, I went looking for a good single meal travel container for Soylent. I found the 20 ounce Blender Bottle to be the perfect size. It holds a tight seal, and when filled with a single meal there is about an inch or so of extra airspace to allow for shaking.
On a related note, the free pitcher that comes with the initial shipment of soylent is just ok. In fact my initial reaction was that it was very cheap. The Soylent logo is provided as a sticker that you have to apply yourself. After using it for a few days, it seems like a better pitcher than my initial impression, but it still seems rather cheap.
My process has been to mix up the entire three meal quantity in the large pitcher and then transfer it to my small single use pitcher each morning. I assume mixed Soylent in the fridge will last three days?