>No, you can't go back once you commit the booleans, but that's the same as CAD packages. Once you commit a fillet or boolean, for example, it is tedious to repair no matter what package you're using.

There is a lot of soft like Space Claim or Solidworks where you can change fillet freely even remove it)
In MOI it is possible to repair practically any kind of objects. And more I can modify them any time I want)

>And no, Modo doesn't do 2 rail sweeps, but it does a lot of other things that CAD packages don't.

2 rail sweep is not only one example of 2D to 3D. All nurbs is based on this concept. Revolve, loft, network, blend, e.t.c...
And yes Sub-D allows to make very complex organic stuff that is very hard or practically impossible to make in MOI.

I have nothing against this soft It looks interesting and people spend their time and efforts to make it I respect this.
But want to look at things objectively :)