Hayden has been beating the drum concerning the use of dollies for storage. He has a great system. I was over at a friend's home. He has a nice shed with a concrete floor and uses similiar dollies. He can push them around with ease and manuever them into proper alignment. I use the Freedom Hitch system and it works very well since I don't have nice sheds and smooth level floors.
About the only drawback to the use of dollies I can think is you are limited where you drop your attachment. Sometimes, I save time not having to go back and forth to a remote jobsite on my property. I just drop the first attachment anywhere and leave them close to where the work is done. With Hayden's system, you have to go back to the barn. But I think I will eventually use storage dollies when I build my shed. Sure saves on space.
Rick