My dad has a fat tire bike and I was able to borrow it this winter cus he had knee surgery. We get a lot of snow here and to be honest I found it very underwhelming. The conditions have to be perfect. It's not very good in fresh snow, wet snow, heavy snow, deep snow... basically anything except packed-down trails in cold conditions. In those conditions it's ok. We have a trail network where a lot of old guys ride on fat bikes so I've had some fun with that, but all the while I felt like my normal mountain bike would have fared just as well on that shit.
Maybe i need to give it another shot but I put studded tires on a dirt bike this season and that's way more fun so I've been riding that lol.