Maybe I should give three stars. They work pretty well, when they work. I've bought a total of five of these pens: three lavenders, & two lemons. The batteries lasted more than long enough, & there was a nice easy draw. It worked best when I would combine it with a sublingual oil with CBD distillate - only, or an oil with high CBD & very low THC. The effect is mild, but it definitely works. And it in no way impairs you at all. The lavender tasted good, the lemon was OK.
The problem seems to be the quality control with the pens themselves. Twice I've gotten one that didn't work: there was no vapor produced at all. The battery indicator light lit up like normal, although after ten seconds the light would blink two or three times, & then shut off.
The first time it happened, I figured it was a rare thing, and the next pen worked fine. But the next one had the same problem. That's a 40% failure rate. You might have better luck, but I can't afford it at that rate. I'll probably move on to a rechargable pen with replaceable cartridges.