Re: which HE washers allow hot hot water?
I think the heat of the water depends on the setting on your water heater, and its capacity, not the washing machine. Or are there washing machines now that heat the water, like a dishwasher does?
A few things to think about before using "hot hot" water ...
-- It's not necessary to adequately sanitize diapers
-- It does harm elastic; the elastic most manufacturers use is rated for up to 100 degrees.
-- Several diaper warranties (such as BumGenius) are voided if your water is hotter than 100 degrees.
Your detergent, and rinsing well (and ASAP after use) are what keeps diapers cleanest. Hot water if they're not rinsed extremely well can just set in what's there.