Just got back in the office and confirmed that we do not use the XT. However, I'm not really sure its necessary.
According to Atwood "The XT heats the water to a much higher temp and we use a mixing valve on the back to mix in cold and bring it down to a useable / safe temp". They both have an 18gph recovery rate based on using gas and electric.
Why heat the water to a higher temp, only to mix it back down to a safe temp, unless you let ME determine the mix" (as in leave it hot enough to scald myself but mix it at the end process) Otherwise I'm already losing some of the benefits of the higher water temp and I'm guessing I'm using a lot more energy to get that limited effect.
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