I have tried all the other apps mentioned in this post and the one I like most is Penultimate.
It is limited. No handwriting recognition and no fancy zooming (I like Notability's zoom features). But for basic note-taking, it is still my favorite. It just seems the smoothest writing experience - and, at the end of the day, that's what counts.
Of course, a good stylus matters. My recent favorite is the New Trent: