I love my mini, but it doesn't like my cinnamon-based vape. The tank is fine, but I noticed that when I unscrew the top to add juice the threads are melting. I don't know whether the top is a different material than the tank, or if it's because of the way it's milled. Currently, it's like fine "hair-like" pieces of plastic coming away. I wipe it down and rinse the cap off before I reattach it, but I'm sure there's a leak in my future. It won't stop me from using them, but I'm looking for a glass/pyrex for my cinnamon.