Winter number 2 update of living with the BMW i3: 44k miles
The heater really and truly was not working, despite what the local dealer said last year. I took it in twice to have them diagnose it and they got an attitude the second time when I insisted it didn't work. This winter I decided I'd had enough and drove it 40 miles to the next nearest dealer - and what do you know? The aux heater was completely nonfunctional. A week later (and a $2000 bill) and my heater is hot enough that it actually will defrost an icy windshield. Hot enough actually, that I had to turn it off on the way home.
On the minus side, now that I have a working aux heater my range has taken a hit. The safety and comfort is worth it though!
The Carmax warranty covered the cost minus a deductible. Between a heated seat failing once, some loose plastic trim, and now the heater fix, the warranty has more than paid for itself twice over. I highly recommend the Carmax warrantys. They truly do cover what they say they will, no questions asked.
The all-season Bridgestone tires are extremely short-lived, and very expensive - about $250 per tire. There are a couple alternatives in overseas markets but nothing here, and no alternative sizes that I can find, unless you can live with wheels that poke out from the bodywork significantly