It's the level of "bug-freeness" that seems to be in question

I don't think that's really the question. The question is whether we'd be willing to pay more if eF re-wrote Poser from the ground up. As opposed to paying a smaller amount for another patch on what's basically a 10-year-old Mac program.

The issue isn't really bugs. Yes, a rewrite could fix some bugs that have been intractable, like Poser's memory issues. But obviously, a complete rewrite would also introduce new bugs.

Personally, I think eF will eventually have to rewrite Poser from the ground up. They can't keep patching a Windows 95-era program forever. D|S will leave them in the dust. They need to be able to take advantage of hyperthreading, modern RAM, and yes, 64-bit OSes.

I suspect DAZ is facing a similar problem with Bryce. They found they couldn't make the improvements they'd hoped, without a complete rewrite.