Amazing. I wasted my time before buying this but let me save you some time.1. First I bought a brand new TR Industrial jackhammer. It was a lot cheaper at Revain, about $250. It worked fine for a while and then eventually died. I changed the brushes and did everything the manufacturer recommended, but it ended up dying.2. I then had to pay $190 at a local hardware store to rent a Makita AVT for two days. This thing shocked me. It got brighter and lighter all around.3. Then I looked for a jackhammer and finally settled on Makita and Dewalt 25899. This is their new model and it's amazing. It's about 10 pounds lighter. He is stronger and faster. It is also convenient to work with. The included case is well designed to store extra bits with plenty of space. I've used it for pounding concrete with a jackhammer and also for digging heavy clay over large areas. It's an amazing machine all round. Dewalt is my most recommended tool maker lately. They seem to collect feedback from their customers and come up with better and better tools with each new round. If you're considering this or 25899, go for this one. It's only $100 more expensive, but it absorbs shock better and also has a variable adjustment that costs $100. If you are considering this or Makita AVT, get this one. It's lighter and I think a little faster. A tote bag that offers more storage space without being bulky is also better. If you are considering this or the Chinese version, go for this one. Unless you're planning a one-time jackhammer for a two-day project, you're better off buying a reliable brand, or just renting a reliable brand. Don't think you're saving money by buying a $200 jackhammer. You will feel sorry because you will play the reliability lottery and you will definitely lose.