The process is a bit easier with concentrates. Simply plunk the included steel wool disc into the crucible chamber, add a dollop of concentrate, and replace the cover. You'll have to take a few initial shallow puffs to melt the concentrate into the disc but after that, just go to town.

Labor intensiveness aside, the Plus has one of the fastest heating elements I've ever used. It takes just three seconds to fully engage. "In addition to not having to wait to vape, you need a quick cool down time to preserve the material in the bowl so that you're not cooking it off while you're not actually ingesting," Firefly CEO Steve Berg explained to Engadget. "So it takes good care of your materials and helps it go a long way."

As such, you're able to really dial in the kind of hit you want by adjusting the temperature range and your draw speed. Since convection vapes like the 2+ continually heat throughout the draw -- ie, the longer you suck on it, the hotter the bowl gets -- you can take little "sips" to enjoy the terpene flavors or give it a good "heeeep" to get a stronger, hotter, and more vapory hit. In general, I found a 10-15 second steady draw granted the best of both worlds.

Adjusting the temperature range is easy so long as you use the associated iOS/Android app. The on-board controls allow you to adjust the range from 320 - 420 degrees in 20 degree increments but doing so is a bit clunky (per the user manual):

Press and hold the right button.

Tap the left button 3 times quickly, just like checking the temperature (while still holding the right button). This puts the Firefly 2 into "temperature setting" mode.

The LED blinks red 1 to 7 times, to indicate what the current set temperature is.

You then have to tap the left button up to seven times while holding down the right to select the desired heat level. Or you can simply use the app and select the exact temperature you want in 10 degree increments. Using the app also expands the available heating range to 200 degrees on the low end.

The app is helpful in other ways as well. It allows you to adjust various settings, see the remaining charge available, and calibrate the unit for more visible vapor. It also offers a number of how-to and instructional videos for vaping neophytes.

Berg assured Engadget that the app will not snoop on your personal data when installed. "We are not collecting data. We have a privacy policy and we're very careful in honoring individual consumers data," he said. And if the company decides to do so in the future, the process would be opt in and "likely cast in the context of helping them better understand their own behaviors and use cases, and how to optimize what they're looking for in their cannabis vaporization experience."

The Firefly 2+ is not for everybody, mind you. Berg points out that users with breathing issues or who simply don't enjoy the act of smoking and vaping would likely be better served by edibles, sublinguals or topical remedies. Conversely, vape users hoping to blow massive clouds should probably look elsewhere.

"If that's what somebody's going for, they may not be best served by a Firefly 2+," Berg explained. "You can turn the temperature up and create a huge cloud but really we're being very thoughtful about cannabis, about the compounds, about delivering a full-service and very comfortable experience. And so that's really where our focus is."

Overall, the plus stands a head and shoulders above Firefly's last model and certainly gives the Pax 3 a run for its money. We're excited to see if the 2+ can breathe new loose leaf life into a market currently dominated by concentrates and edibles.