Jason is the Reverse Osmosis expert for Serv-all, the Water Treatment Division of Water Quality Plumbing. He was careful, thorough, honest and very knowledgeable. He also removed another (unnecessary, as it turned out) filter we had been sold for our refrigerator. It continually leaked. In fact, the last plumber we had out had simply shut it off, without telling us. Jason also redid and simplified our shut-off valves. Then, while waiting to make sure there were no leaks, he cleaned up and removed our old system. I highly recommend him.