I have a few of the SQ’s both 18650 and 217’s this one is by far the most stunning, the engravings are actually engravings and not just printed on the door and body, as for how it performs it’s the best squonking device I have, it out performs my purge well there is no comparison really. I prefer the 217 over my 18650 just based on the ability to use a bigger battery and the larger squonk bottle, granted the 18650 version fits better in the hand but with the 217 I know I can go out and not worry about taking a second battery or a bottle of juice, so why 4* considering all the positive point we’ll that will be down to customer service, the SQ’s have one slight issue and that is over time I find that the contact that touches the brass nut on the 510 pin leaves a slight ridge so I every now and then I use a very fine craft file to smooth off the ridge this as you can imagine overtime flattens the side os the nut, so I have emailed On a few occasions the price of purchasing replacement brass nuts and a upper battery contact to date I haven’t had the courtesy of a reply hence 4*