Another notebook app on promotion right now: CaptureNotes 2 can be had for 0.79€ ($ 0.99). So I couldn't resist giving it a try.
I will try to post a more complete review tonight, but for handwriting it is far behind Noteshelf. It does have some interesting features that Noteshelf doesn't have though, especially the option of importing pdf files for annotation.
Here is MacWorld's review:
http://www.macworld.com/appguide/app.html?id=1179516