Good info, and definitely food for thought.  Please forgive me for waxing philosophical here a bit.  My approach to evaluating software (3D or not) is based on my theory of knowledge:

Met cognition: how to learn anything

1. What are my basic facts (nouns)?

2. What are my basic actions (verbs)?

3. In what order, with what tweaks, do I perform these (grammar, declinations)?

 Works for a foreign language, chemistry, physics, math, 3d software,…

Now for 3D software the question is: given that time is limited, what are the basic things I (as a rookie amateur with aspirations) want to checkout?

For me, for modeling:  (a) Make a cube.  Add and take away polygons.  Round some edges.  Extrude and bevel.  (b) Make a cylinder.  Do the same as the cube.  Then round off the body of the cylinder and make a gear (Silo3D was really disappointing here).

I still have to come up with a set of basic things for those operations beyond the modeling.  Access to systematic training materials and ease of use count.

Any suggestions for what basics to learn and try out to do a (relatively quick) software evaluation?