I haven't counted hits, but me and a friend who doesn't own a vape got 6 bowls and more battery left. The bowls are small so they vape fairly quickly. Probably about 6-8 hits per bowl if we are stretching it, maybe 5-7 actually? The ABV always comes out nice and even etc. He has hated every vape since trying the pax because the pax was so easy it was his favorite. When I asked him if he loves this more than the pax like I do, he said "well yeah whats hard about pressing a button and inhaling", so that gives you an idea of how little technique/learning curve there is.
The best part is those 6 bowls in this, probably make up less than 2 pax loads, and are certainly not less effective than a pax load. I wanna say based on my non-scientific findings that this thing is ~3-4x more efficient than the pax in MY personal use. I feel 1 bowl of this firefly = 1 pax bowl as far as effects go, but the pax has no flavor to me, and uses 3-4x more bud per bowl.
I really don't know that I needed the 2nd battery since I just top it up whenever needed (never so far) but it only takes 20 min or so to charge to full if you've had a couple bowls. Loving every single thing about this vape so far.