I'm on the fence with the Pax 3 and Firefly 2+, what swayed you?
I've used both - in theory I'd prefer the firefly since I really just like to take one hit or two then come back another time for the rest, but the firefly just didn't work great in my experience. User error no doubt, but I tried a lot and couldn't get the hang of it.
The Pax3 is very simple to use and works great. I don't use it much, but anytime I'm looking for a stronger buzz, that's what I go for. It still doesn't hold much since you can load it half full, I'm just a lightweight.