The best 3d app for you is the one that you feel comfortable using it. So try out the ones that you can download as of demo, and see which app fit you the best.
Here's the link to some 3d apps compatalbe with Mac:
Pure Mac: 3D & Animation - Software for Macintosh
And also Houdini for Mac beta is now available.
http://www.sidefx.com/index.php?opti...15&Ite mid=66