Everyone's experience and opinions will vary - surprise. I've found Vue to be pretty stable, especially on an underpowered system. It's crashed a couple of times but I'm hard pressed to think of many application that hasn't crashed once or twice -OK SQL Server & maybe Solitaire.

Paradoxically, I think that the higher end applications may be better performing at the hardware margins because the are likely to be more efficient in their use of resources (generalization). Poser has long been known/suspected of memory leaks etc. Many of the bugs like the obj export focus bug were carried over to at least 6 (if I recall posts here correctly) and possibly 7 I don't know if it was fixed in 8. Bolting external modules like the face room to that base probably didn't help matters. 

Some applications may be useable even somewhat below the minimums, but I suspect that with Poser the minimum specs are indeed understated. They could clear things up by giving some benchmarks. That would allow people with lower end systems to make an intelligent buying decision rather than end up disappointed.

Note: Daz Studio 3 Minimums: 1.3GHz/1GB OpenGL 1.3+128 MB RAM.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken