I have been pleasantly surprised, I've been out putting my 450i to work as cold as -20°f. It had started as quickly as it does in warmer temps and the efi sensors do their thing at the engine warms. Shifting is no knotchier than warm temps and the 2wd/4wd/4wd-lock works perfect.
What is more surprising is that I haven't broken anything, banging around in the woods, skidding tree length logs (18"butt x 75' to a 4" top white pine), well beyond the rated towing capacity, Trygg chains on the tires
turns out, this is the best tractor I have ever owned