I have read a few reviews from people stating that tea pigs teabags loose their potency quite quickly. I believe this may because, like all tea, they should be kept in an air tight container. I personally have had no problems since doing so. However its fairly common knowledge that tea leaves are best kept in a dark jar, away from strong light sources and so I'm surprised tea pigs have provided a glass jar??
That said the jar is air tight and looks lovely.