The two serve a different purpose. No one thinks a Harvard MBA gives you an edge for bootstrapping your startup in your garage, and no one believes doing Techstars will help you run the division of a large corporation.

A better decision algorithm would be:

  1) figure out what you want to do in the future
  2) pick acoordingly

If you want my take on MBA vs. entrepreneurship, I blogged here (http://blog.fairsoftware.net/2009/08/12/the-cheapest-mba-pro...). Guess what: for entrepreneurs, taking the entrepreneurial route is better.