Although this doesn't address your question- Toyota abandoned leather for the 2012 Prius line- they use "softex" as their high end seating option.
my 2010 didn't come with leather and i had it installed with heated seats.was much less than factory install and from what i have seen from factory installed ones, mine is a much better fit.i did it three years ago when i purchased the car and it looks just as good now as when it was installed.
The IV for 2010 is the lowest model that came with heated seats. If you see the sticky regarding the 2012 changes, heated seats aren't mentioned...so I would have to believe that the "three" won't have heated seats.
I've seen one in my garage. wait, scratch that, as others have said, the prius no longer offers leather, but "softex"
