I have had one of these for 2 year + now and everyday heavy use, still works great.
A few tips...
400 Degrees is too high, you want to avoid Benzene, which starts at 392 degrees F...
this chart was found here,
LiftMJ | Owen Smith's Writings and Graphic Art, for those that prefer to source their own material.
You do want to give it 5-10 mins to warm up, but with the ground up weed in the bowl., here is my protocol...
1. turn on vape, set to 370 degrees F.
2. Prepare weed, fine grind, put in bowl, maybe 1/4-1/2" deep (find your personal preference)
3. but bag stem and bag on
4. let sit 'warming up' for 5-10 mins, I notice if i leave weed in their for a bit before hand it vapes much thicker.
5. Turn on fan to fill up bag
6. GET HIGH!
One VERY small problem I have with this unit, and it may just be mine, not sure if systemic. If i leave it sitting for a bit at a temperature setting and then turn the fan on, the temperature reads the set temperature, but then if you hit up or down suddenly the indicated temperature shows 10-20 degrees warmer then set point, then gradually cools down. It is almost like a software bug.
Overall this was a great investment for me. I just wish I looked around before buying, could have saved myself $100, I have seen these for less then $200 on various sites.