There was a question from someone here, about if the gel insert would get harder in low temperatures.
The lowest temperature the bike was left out in, was uppers 30's F., and I did not notice any difference in the seat, can't say if it will be a factor in lower temps, winter in Phoenix is not real world cold, compared to where a majority of riders reside.
After 7 months of daily use, I can say that I feel it is worthwhile to install a gel insert.