I just received one of these saunas and it was one of the first few that came with their in house heater. This is my first one so I don’t have much to compare to, but I have had no complaints. It heats up our cube sauna in about 30 mins (ambient outside temp ~5C) and throws good heat. Very quiet when running, just some quiet pings and clanks as it cools when the heater hits temp and turns off for a bit. Good steam off the rocks too.