Well, I think I can give you some taste of the problems... I started learning 3D some time ago or so with both Blender and C4D. Now Im learning polygon modeling, alpha channels and volumetric light in C4D while I just solved some basic problems with saving the files in Blender... :P It seems the main problem with Blenderis that its extremely "idiomatic", it has its own logic that is not necessarily my one:) Also, Blender produces a set of fabulous problems on my computer, where both LW and C4D worked well. I think the first thing you must be prepared for when trying Blender will be the enormous work at the very beginning. I tried and I decided to focus on C4D, its far far more intuitive although not perfect. It seems also that Blender is less powerful-for example, it just got a raytracer...