I think you should think of what you want to learn in the end. I started out hoping to just make models, so i went an easy way. made a few bad models and faced i needed to learn something better. I am trying to use blender as it will be usefull when i know how to use it.
I tested milkshape and made a few trees in like 30 min after opening the program for the first time. I guess that sumens it up well.
If you need to make less complicated models you could just make them in radiant and convert them to .ase models as well.