AudioNotes

I am not an owner of either brands, but, I hang out a lot at a shop that carries both brands. The Harbeths have a tighter, more accurate bass response and deliver a reasonably detailed and lively sound while being on the warmer side compared to many current speaker designs. My only big 'issue' with the sound is that there is a slight raspiness or sibilant edge to vocals, but, other listeners like that little bit of crispness to the sound.
Audionote speakers tend to have a somewhat overblown upper bass response, particularly when they are placed in the corners of the room (position recommended by the manufacturer). The overall sound is even warmer than that of the Harbeth, although it manages to substantially avoid the muffled and lifeless sound (like someone threw a blanket over the speaker) that often attends 'warmer' sound. I don't think the Audionote would beat the Harbeth in any kind of beauty contest where a comparison is made category by category. Yet, for me anyway, for the shear pleasure from the overall sound, I prefer the Audionote speakers--there is 'something' there that makes the music seem to blossum and fill the room. The other plus, for my taste, is that they work reasonably well with the lower-powered tube amps.
For the Harbeths to sound their best, they do need to be well out into the room. They image beautifully there. The Audionotes, which are meant to be nearer the corners of the room, don't quite deliver the same kind of depth to the image in that placement. If you are someone who places a high priority on 'imaging' and can accomodate the space requirement of the Harbeths, that might be another thing to factor into your choice.
I have only heard the Harbeths with one solid state amp (Bel Canto) and the Audionote only with tube amps, but I suspect that both would be quite good with solid state because both have a warm sound that is 'forgiving' in nature.