Water Pillows

I went to Vegas a few months back and brought some cigars home with me. I bought a few pillows for the trip home and was just curious as to how long they last. My brother says as long as they're filled they're good, is that true?

I saw one guy at my B&M who had one it wasn't in the pouch, and it looked brownish, he claimed it was because he took his cigars out of the cello. I usually use the boveda pouches but they didn't have any at the time. I know they were only a buck but I dont want to throw them out if they are still good.