Steve,
Cutoff bandsaws can give decent results. With a good sharp 1" wide blade, and a properly squared vice, I can get cuts that are square (in that 5.5" diameter) within the waviness factor of the cut. This would mean about .020" minimum facing allowance on each side of the blank.
It sounds like you intend to use a hand fed saw. That can get mighty strenuous, mighty quickly. You'll have big biceps and pectorals when you get done, though
Keith made a good suggestion. When you don't have a shop full of tools of your own, it makes sense to let someone handle it who has the proper equipment. Believe me, it is no sweat for a big bandsaw to cut that size of stock, although they might be a bit more rammy, and you might need 1/8" of stock allowance to guarantee cleanup.
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)