Pros and cons to both and both require proper investigation and research to see which one is right for your particular situation. In very cold climates, regardless of which you use, you will still need good insulation in the room it is parked in, if anything but to protect the water lines.
If you have a water tank, ensure you have 1 or 2 ample-sized floor drains and the tank is set on a cement pad that is poured so it directs water to the floor drains. Helps prevent flooding should the tank have a problem. Efficiency improves if you wrap a tank in a water tank blanket.
We want to renovate our tack/feed/storage room next fall too. We did not build it and don’t like what’s there and not heated. We want a cement floor with in-floor heating. Easy to maintain and keep clean. It’s a good time to install floor drains and add hot water, wash tub, and since I also want a new washing machine in the house, the old one can go out there too.
Oh, if DH only knew the extent of the wish list! LOL (Actually, if money were no object, I’d install in-floor heating the entire length of the barn aisle just to help keep the ambient air 1 or 2 degrees above freezing. Now, where’s that lottery ticket…)