By some people's standards, I guess Blender could be considered usable on OS4/SAM 440ep, and to be fair the version I used was one of the very early OS4 releases so perhaps I should give it a little more leeway. I don't do a whole lot of 3d rendering anyways, and any that I do is generally done in programs I am already more familiar with, programs that get the job done 100x quicker and better on my 4+ ghz SLI PC. One crash is too many crashes when I have other options, so I got annoyed quickly with the fact it had a habit of crashing/locking up when I tried to save/load projects on the OS4 version. Blender is likely a lot more stable now for OS4, but when I tried it it was not much more than a novelty to me, was too unstable to really use - but again, that was likely one of the very first OS4 releases.
I'm a bit picky about software stability, especially if there is a PC counterpart/version I can run. Some folks are head over heels in love with Blender, where as I find it a bit oddball to use interface wise on any of the platforms it comes on, be it OS4, Windows, or Linux.