I presume NeoOffice is stable - unlike the OO version ?
You'd have to try it with documents that cause OOo problems on your system. It's based on OOo 3.0.1, and it's a .0 version, so if you are looking for high reliability I recommend waiting for 3.0.1 or 3.1 minimum.
I've never felt the need to use OOo since NeoOffice arrived, so I can't comment on OOo's stability. As I say, I have avoided NeoOffice as much as possible as well. I find iWork does all I need in that space, except when I occasionally want to open a complex MS Office doc. I haven't noticed any instability when I have needed to use it.