Anyone Tried Herb Preserve Stash Jars?

I've been thinking about getting an Herb Preserve for my stash jar, and now that they're doing the new special where they are giving away a free jar with every order, I think I'm going to jump and buy one. www.herbpreserve.com Has anyone tried them? Do they really keep your stash fresh for six months? I am a pretty casual smoker. A quad lasts me about 3 months, so this seems like a good investment. What do you think? Also, does anyone have any coupon codes?