I have seen and used some GREAT shipping container offices, deer lease cabins, and even a bunk house. Maybe you know exactly what you are need, but for me, 8' exterior dimensions for a workshop sets off alarm bells.
8' Exterior, the steel is thin, but the corrugation and frame make the interior about 7' 6"....before you start adding insulation and interior wallboard of some kind, so with 5" to 6" on each side means you are down to 6' 6" wide. 32' deep work bench on one wall...that gets you down to 3' 10" from the edge of the bench to the opposite wall. If you will have a chair or stool to work from, 3' is the normal minimum clearance used between the back of a desk and the wall...and this does not allow room for someone to walk between the seated person and the wall.
You'll basically have zero room opposite the desk for any kind of storage. Depending on what you are doing at the bench, it might be great or you might be tight maneuvering materials.
A ham radio shack, electronics workbench, reloading bench, and similar desktop hobbies will probably work fine. I would think that anything involving building materials would get pretty tight.
Just my 2 cents worth.