I was with OOO for years before I got a great deal on Office 2010, but I never stopped using Onenote. It's worth twice the price to me. I mostly keep my eye on alternatives so I don't have to put up with MS dictating to me what I do and don't need. They get all obsessed about making a notes product that fits inside their package instead of just making a great notes product, thus making it unnecessarily hard to make very basic formatting decisions (paragraph spacing) inside onenote because they don't want it to step on Word's toes.
Evernote is nice, and that's the feature set that's easier to find, especially on mobile/web. Cloud notes, web clipping, all the stuff that doesn't interest me much. My wants are pretty basic, and I keep thinking I really should learn enough of a portable language to maintain them myself.