Anything you ship to Mars takes the place of something else you could have shipped to Mars, no matter how it gets there, so it needs to have a high utility.
The other complication for an m2 radiation shield is that it would be slightly propulsive, which would slightly complicate planning trajectory planning (though not badly so).
The other complication for an m2 radiation shield is that it would be slightly propulsive, which would slightly complicate planning trajectory planning (though not badly so).