Tobbacopipes.com is where I buy from and i absolutely love them. Bought a Molina Peppino the the stem was too tight, smoked 3 bowls from it, freezer to see if it would loosen... they replaced it no issues. I actually sent it to their other address, the guy looked up my tracking number and sent out the replacement before they even received my package. Heat? I am not refined enough to notice differences but I probably break all the rules. I have a camper by the shore. I have a huge bag "my purse " in my wife's words. In it is all my pipes and 30ish tobacco varieties, all I own. Tins and bulk plastic bags. East coast US 90 something degrees, heavy humidity. My car will sit on a parking garage for 16hrs before I drive to beach at night. Then it sits next to me everywhere I go and I am outside till bedtime. I haven't noticed a real difference, probably inhaling some plastic toxins but I like to constantly smoke different types so the trade off for now is worth it. From day one to a month or 2 of doing this per tobacco, I am not seeing major changes even with the humidity of the tobacco. I smoke A LOT during a day, so everything is being opened to pack a bowl at least 1 x in a 2-day period. I haven't cellered anything yet so I would bet good money that what I am doing isn't good for longterm cellaring.