Attached Link: www.wings3d.com

Wings3D happens to come in Mac & Linux flavors as well as PC.

No 100% guarantees with Macs though, since OpenGL performance seems to vary quite a bit depending on video card and OS version. (Seems they have some issues getting the drivers just right.) Shouldn't hurt to try though, I've had the Mac version working fine.

As for my best way of describing it? It's simple enough for beginners, yet robust enough for pros. Doesn't cost a dime, so go and get it already. Plenty of tutorials here and at it's Official Development Forum, not to mention expert users willing to lend advice. Exports to .obj & .3ds which will complement your use of Bryce & Poser.

I also recommend using a mouse other than the one-button one that Macs come with for modeling.

---

Barbequed Pixels?

Your friendly neighborhood Wings3D nut.
Also feel free to browse my freebies at ShareCG.
There might be something worth downloading.