I keep a PT with a manual carto in my car charger all the time. The past few mornings have been in the 30s (just a bit on the cool side) I've noticed a strange thing with the cartos. There is more vapor production and they last longer. In the afternoon when the car is warmer, the carto will start to get that burnt taste but I forget to bring it in the house. The next morning it's fine again, and I sometimes get juiced.8-o I wonder if the cartos should be stored in the fridge? anyone else notice this?