There seems to be quite a few on Priuschat that have been using these batteries for a while without problems, many that seem to be old timers on the forum.
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The qualms I have is #1, LiFePO4 shouldn't last in freezing cold weather. We have freezing temperatures 9 months out of the year, and sometimes a snow here and there in the summer.
And #2, the housing is plastic. I don't think that would be good for thermal management.
If I could make a mold of the module housings and cast them in aluminum and add some sort of heater for the winter, I would go with these. But that seems like a lot of work.