Amen!
If we're going to do humans to Mars, there will need to be robotic precursors. And that mass-producing and mass-launching (RTG-powered) MERs would be a great way to do it.
If these things were rolling off an actual production line, how expensive do you suppose they would be? How much of their cost was R&D, which could be ammortized with successive flights? How much cost-savings could production-line manufacturing create?
Cheers,
Nathan