"Uh, Bob, if it's about actual Return On Investment, I'll choose Door Number Two, which is two 5DII's, (main and backup), and three prime L Canon lenses, which brings me to about $8,500, and I'd use the other $21,500 for Testing, and for Promotion, and an efficient, well-designed website."
yes curtain #3 is probably the most selected and that's where Bob usually keeps the big prize, the unmentionable c word (canon).
of course when I said $30,000 I was just talking about the digital back, not really including the lenses, learning curve or beta testing investment, so for a lot of uses make that $40,000 to $55,000, depending on the euro, the new worldwide standard for currency calculations in the world of medium format.
the red entering the medium format world in quarter whatever 2010 probably won't change much today, but money and time spent today can alter a career.
whether you have selected curtain 3, or gone for that big ticket item behind curtain 1, it would probably be a good idea to invest $3,500 for the 5dII and also add a copy of "final cut pro for the beginner" to the list.