I use a chest freezer, an old one I picked up off the side of the road for free.
I leave the temp probe dangling between the kegs, about halfway down. Haven't had any issues with kegs freezing, but occasionally do with my lines freezing. It's usually only when i put a new warm keg in and the freezer has to run for a while to chill it down.
Lifting kegs in/out isn't an issue for me, they weight about 20kg full so it's not the heaviest thing in the world. Obviously though not everyone is keen on that.
Collars become advantageous, even if you're just using a pluto, as they let you pop your gas cylinder outside of the unit and you can just drill a hole to run the gas line through. I have a manifold screwed to my timber collar, so it's just one line in and then it splits from there.
Be careful with the Keg King fridges, I don't have personal experience with them but from what I've heard/read they're not very good. They're basically just a bar fridge too, which suggest to me that they'll use a lot of power. I particularly like the chest freezer option for this reason.
For those that worry about excessive cycling, if you have a bit of mass in your freezer then I wouldn't imagine it'd be much worse than letting it run as a freezer. I have a chest freezer full of meat/groceries in the other room, and I reckon it runs more than my keezer does.