They are all good at certain tasks, and all need inovation for other tasks.... hehe
I think it is truly up to the end user for just which app works best for them... unless of course said end user is about to land a job with some company which utilizes specific solutions... in which case...
a) if you are good enough to land a job doing 3D then you probably don't need further advice on most any set of tools currently out there...
b) you probably are satisfied with the toolset which afforded you the opputunity to land such job
Other wise, just try them all out before making any purchase decisions... I know of many C4D, Maya, XSI, LW user's who rely on Wings3D, Clay, and/or Silo for thier quick concept modeling, especially for organics, and then take things into ZBrush, Body Paint, and/or Deep Paint for texturing, and then further into thier big app for other tasks.... I think it's rare these days that a pipeline is limited to one solution... rather you will find that many companies who are into high end 3D are using upwards to a whole handful of available solutions

Even companies such as Weta, who are highly reliant on apps such as Mirai, look to other apps to include into the ol pipeline for many tasks
and let's not forget 2d apps such as Photoshop, Painter etc...
The moral of this story is.... perhaps no one solution exists in the wonderful world of 3D... and no matter which app you choose to get, there will still be something you will soon find needing inorder to realize your ultimate 3d fantasies
PS... if I was personaly going to get an app which supported Nurbs, I would also want said app to have polyspline, polyline, and subd tools as well
Happy Exploring
