Cannabis Delivery Methods

I just saw a short mention in Esquire magazine about using dosist vape pens to dispense cannabis in formulas to obtain specific results: bliss, sleep, calm, relief, arouse and passion. To make sure each dose is exactly the same, the pen vibrates when it’s time to stop inhaling. What are your experiences with this type of delivery method? Does it give enough control for use in a medical setting? What other delivery methods are you finding the most effective?