There's a few different sub models out now, one is made for herb, one is made for dabs, one goes both ways. The extraction is very good, but it's debatable whether it works as advertised. Imo as it separates into sublimate the resulting vapor is incomplete in its spectrum, requiring more work to get all of the effects out of your herb because you have to dab the sublimate separately. The adapt-a-bong works great with water, or you get the kit with the launchtube which is a dry hitter. It's fun to use it that way if you're into the ritual of it all, but if not it's just an extra hassle. One big thing that makes herbie superior to both the evo and the sub is it heats up ~instantly from a cold start. The sub and the evo both take significant time to warm up, and also have an auto shutoff so they can be inconvenient to use if you're in a hurry.
