Not every time, but a lot of times, vapor starts coming out of the stem when I hit about 160. I wouldn't rely on that sign though. Also depends on the torch used and even then, it depends on how exactly you are holding the block to the flame for how quickly/slowly it will heat up. The propane torch that I picked up/people recommend for this vape will put the block up to 180-185 when I stop heating at 165 for instance, and heats the block much faster when I angle the flame just right. My butane torch however, would probably only push the block to 172-175 if I stopped at 165. Too many variables to not need the temperature readout. Not to mention letting you know when you want to reheat and for how long.
That stuff aside, as more time goes on with this fellah, it has definitely become my go to device at home. The vape signature is so unique, so powerful. I almost want to say I feel more at peace/calm when I use this device over other vape signatures. I thought that unique feeling would fade, but so far, it has persisted. Pretty happy about it, and to be a part of this Supreme family. Peace guys, have a good one.