Original Review: 1 star. I was really excited to get this grinder. I read all sorts of great reviews on Amazon and many other websites. I felt confident this would be a great auto grinder to ease my old arthritic hands. It worked a whopping 9 times, the 10th time, it just slowed to nothing like a dead battery, as it had previously when needing a charge after each use. I thought this was odd, a 2000mAh lithium ion battery needing a charge after each use, odd that it barely made it through grinding enough for a cone before needing a charge. Anyways, I charged it overnight. The next morning, it started up, made a quarter drum rotation empty and the motor died out like the battery was dead already. I tried a different charger, different cable, different wall socket. 12 hours later, I gave it another try empty. Same thing, 1/4 turn dead. I tried a third charger, wire, outlet, 10 hours, same thing. Definitely dead. $45 for 9 uses, $5 per grind. Not worth it. $45 is the cost of a decent quality half at my local dispensary, I would have rather suffered the arthritis pain of 9 grinds and had the half as opposed to throwing the same money away at something that is now going to contribute to our current landfill issue, plus the environmental hazards of the lithium ion battery disposal.1st Verdict: a waste of $45, landfill fodder and lithium-ion battery environmental impact = product to avoid.Update 6/20/23: +2 stars for great customer service. I was promptly contacted by Mamba Grinders, after explaining the issue, and information and photos exchanged, a copacetic resolution was quickly offered. Mamba Grinders stands behind they’re warranty and are sending me a replacement unit. I will follow up with further updates.Update 7/15/23: +2 more stars for quick shipping on the replacement grinder. After giving this one a full charge, it was obvious from the first grind it had far more power than my first one. The new one grinds with much more torque and less reversing to unbind. I tried with both the old cap and the new to see if the grinding cap made a difference, it did not. It must have been a battery issue with a certain batch. I have used this every day for 21 days, no change in performance, battery holds up so far.2nd Verdict: worth every bit of the cost. When not a defective unit, it works great! Smooth consistent grinds, a ton of keef. I grind for my desktop vape and it’s perfect. Now I love this grinder. No more sore old stoner hands from my hand grinder.Final update: 12/7/23 I have used the grinder nearly daily for the past 6 months. Still working perfectly, battery holds a good long charge. Long enough that I usually can’t recall the last time I charged it. The grind is fine for use in a vape or to roll. Great grinder. Highly recommend..