I've been reading and looking at many sites trying to figure out which vaporizer fits my criteria or comes close. I've looked at PAX, Da Vinchi, FireFly, and others and am just more confused now. Here is my criteria in order of priority: 1. Efficiency - I have to travel a long way for product and need to maximize what I have. 2. Reliability - I don't want to have to mess with it much. I don't mind cleaning it and maintenance, but I need it to work when I need it to work. (I'm sure this is a given) 3. Heat up time. I am looking for something that I don't have to wait long for it to heat up before being able to vape. 4. Learning Curve - Not sure if this is a real issue after I learn the best method of using it. But initially the Efficiency is a concern. 5. Portability 6. Cost - could do more but want to keep it around $300. If it is more, I would be ok if it is truly a great vaporizer. Most of the time it is only me taking a hit or two.