Yeah Blender is my main modeling program even if i own Silo 2 !
Once you've practiced some with it you can't live it !

Now the 3D engine in it , is slow , not for hight resolutions and big scenes !
Let's wait future if they can bring a powerfull 3D renderer in it ?
But Crystal space is not the most powerfull indie engine (i've tested some
demos and not convinced in frame rate with very simple scenes) !