We use this printer at a small business to print our order slips. The printer has worked exceedingly well so far after about eight weeks of constant use. The customer support from Rongta has been exceptional, and we are pleasantly surprised at how helpful they are.Here are our thoughts about the RPP300 printer:Pros:1. The unit comes with driver software and with an SDK for custom programming. They also provide demo software so you can get up to speed quickly to write your own apps for this printer. The only problem was a minor one. Android Studio would give warnings about the Chinese characters in the demo code comments. It's easy enough to delete the comments containing Chinese characters and the warnings will disappear.2. The printer is small and lightweight. It comes with a convenient belt hook and you hardly even notice that the printer is there hanging from your belt.3. The print speed is very fast, so you can take care of customers quickly.4. The battery seems to last for many days before recharging is required. The battery pack is replaceable, so you can keep a spare battery already charged.5. The customer service is the most responsive we have ever known. We have bought several Epson printers in the past, but Epson's support is not nearly as responsive. We will choose Rongta printers first over Epson now.6. The price of this printer is surprisingly reasonable, and it seems to be an excellent value.7. The printer can charge through the USB connector, so you can connect a power bank to the printer in case someone forgets to charge the printer. (This happened to us already.)8. Our customers are pleased at having a new electronic system. We had been using pre-printed books of order slips, but the Rongta RPP300 has helped us cut costs. Those pre-printed books were expensive, so the Rongta RPP300 helps us save 75% over the price of those books. The savings pay for the printer in just a few months.Cons:1. The only trouble for us is that the maximum paper roll diameter is 40 mm, and the yellow paper we use is not available in small rolls. However, the small roll capacity allows the printer to be a small size so that it does not get in the way when wearing the printer on a belt loop.2. Once in a great while there will be some radio interference in the communication and one or two unintended spurious characters will print. This, however, is an unavoidable problem with wireless communication when interference is present. (We have many motors and industrial machines operating near the printer.)So far we have printed many thousands of order slips, and we are very, very pleased. Kudos to you for your excellent product, Rongta!