Ozarkhen,
A word of caution about round bales. I don't mean to be presumptuous, you may know this already but if not I hope it helps. Please make sure you keep your round bales stored in a completely dry place where they will not get any moisture on them. Wrapping them doesn't work since that actually traps the moisture that the grasses release during the drying that it continues to go through. Round bales will mold from the inside out as well. I understand what you mean by rolling it out, and it is a fabulous idea as long as you keep your spare bale dry, or you are going to be overwhelmed with all sorts of mold spores. I just went through this myself. I wound up loosing about 25% of the hay at least from my round bales because I didn't store it just the right way. Hope this helps,
Rachel