I had EZ Flow Plumbing out for RO and a soft water system installation awhile back and was very happy with their work. Keep in mind they were not the cheapest but they were price in middle and dependable. My water heater went this month and needed a replacement water heater and EZ Flow was there same day service and replace the water which was 10 yrs old.
Remember people you get what you pay for I've always found EZ Flow very reasonable in price, and the service is AAA+ quality.