While a heat pump can help in the fall and in the spring, they aren't all that great in cold winters. Considering I lost 25% of range, it's not terrible. By comparison, my gas powered Civic lost 16% of its range in the winter, so 9% worst with what is basically a large hair dryer is very good IMO.
I haven't done any testing beyond what I've needed...I live in Northern Ontario so heat is not that much of an issue.
Just saying it hasn't been a big deal for what I've needed so far.
I don't have it and have not had any thermal issues thus far...I tow occasionally an ATV and have had decent charging speeds when charging (125-140 kWh charging speeds).
Honestly, I was a bit worried when I didn't get it at first, but I'm not really regretting it after two months of use.