We have a 40x70 Quonset that is our only building/shop. we do quite a bit of stuff in it, but our biggest complaint its because of the curve, you cant put anything of decent height close to the walls, Dad and I both have decent sized toolboxes, the typical top/bottom cabinets and they both have to set out from the wall about 24" I would guess. You start to loose alot of space in a hurry with one, Id bet that if we had a pole building the same size it would feel huge because of all the extra space wed gain. Just figure on everything having a foot or more of basically empty almost unuseable space behind it.  Also its really hard to get much big equipment in one because you run out of height.  

The only way Id put another up is if you built stem walls about 5' high and then built the quonset on top of that. But then Im sure youd be higher than a pole building.

But you do learn the art of packing and tucking things into places you wouldnt even think theyd go lol