Thoughts on two jobs

I recently received an offer at two firms. One is a physical commodity trader of lumber (no futures or series certifications they are market makers of physical lumber. Their clients physically take possession of the timber) and the other is a Middle office role at Fidelity (I know I'm not supposed to include the name of the firm but I didn't know what to describe it as other than an asset manager). I am not sure which to choose. The cultures seem equivalent and the work equally about as interesting. If I went the middle office route I would choose to continue networking and pursuing a CFA to attain a Portfolio Management Role. I have reservations about both positions. For the physical commodity trading role, I am worried that I am pigeonholing myself into the lumber industry and will be screwed if lumber becomes obsolete. Is this true? I am especially concerned with this as the majority of traders at this firm make about 400-500K but spend their entire career at the firm never learning another skill. My concern is that if wood becomes obsolete in say 30 yrs that I will not have transferable skills to make even a lateral move to a different commodity house. Also, this being said, would it be possible to leverage the experience in a trading role at a MM? I am from a non-target. On the other hand in the middle office, I am worried I will never make it to the front office especially considering it is a ' dying' industry. Any thought??