Machines our here get used daily. At less than around -20 many of them begin having starting problems. -15 is generally okay; -25 gets iffy. The new EFI Honda ATVs are worse than the older carbureted models. Many of the newer snowmachines which are supposed to run cleaner have a difficult time without adding heat. A heat gun is a wonderfully simple and useful tool in the cold. You quickly discover that most battery chargers and other electric devices don't have insulation on their wires that are good for much in terms of deep temps though.
I was contemplating a four stroke 'Cat a couple of years ago with some concern about starting in severe cold. They had an accessory package that would automatically start the motor and warm it up whenever it began to get too cold. It was supposed to prevent cold start-up problems resulting from being left overnight at -30 or whatever.

Here's mine sitting in the driveway.


Spring in Petersville.