Personally, I wouldn't give more than about $10-15 for the case by itself, but I'm cheap and I don't play along with the "It says SO on it, so it must be worth $$$" game.
Looks to me as no more than an inexpensive plastic case that has no organizers or foam padding inside (may have been removed) that SO slapped a badge on. I agree, most of the tools are junk, mostly dollar store or cheap auto parts store grade stuff.