I have used/experimented with a protected Li-on in my Vamo. I ended the experiment when, after a slight chain-vaping session, I could feel the battery getting warm through the stainless steel tube. It wasn't hot, hot mind you, but it was significantly warm, warmer than I was comfortable with anyway. And, although this could have been just my imagination, it seemed to be getting the hottest down at the negative end of the battery. I have since decided that I will only use a good quality IMR in this device.
