I need to update this thread with all the ideas I have been thinking about. I will take some time this weekend to do this. It looks like my quessestimation was way off in four major areas.
1. Cost of the MX-28 is only about 220.00 USD
2. Cost of assembly for the DARwIn-OP is way higher than I thought.
3. Cost of metal brackets is also higher than I thought.
4. You are also paying for a 2 year warranty.
Other guys part 1.
Other guys part 2.
Other guys part 3.