Harbeth vs Vandersteen vs Sonner

One thing I can say about Harbeth in comparison to others (not necessarily the other speakers you are considering), is that when comparing them, other speakers can sound more "exciting", "involving", or any number of similar adjectives used to describe what some will define as "better."
The goal with the Harbeth sound is accuracy and neutrality.  They are designed to not add anything to the sound that was not part of the original recording.  For listeners of rock, this can be less exciting than other speakers that accentuate different frequencies to add body, warmth or excitement.  
For listeners of jazz, acoustic based music or vocals, there is not much better than Harbeth.  
I do not advocate that you buy Harbeth, even though they are the best speakers I have owned (I've owned several pairs).  BTW, I also own a pair of Sonus Fabers that I find to be fantastic.  While they share some things with Harbeth, I would not say the SF speakers sound anything like the Harbeths, and definitely not as good IMHO.  Still, I enjoy them for the simple reason of them sounding good in the room I am using them.  
The one thing I will say in favor of Harbeth is that they are very popular, and can be somewhat hard to find right now.  This is not a bad thing, in that they are easy to sell if you change your mind later, and they tend to hold their value better than many other brands.  
Whatever you decide, please make sure to share your findings here.  
Happy listening!
Peter

snackeyp, what do you like better with Harbeth than SF? What SF do you have? And most important question: in moderately sized room (12’X25' with listening position 15’ from the front 12’ wall) what Harbeth model will be a best buy (price performance) for acoustical/vocal jazz and blues?
Thank you.

@OP,
Great to hear your new system is up and running and that you love it!
Vandy,  Aesthetix, and AQ make a great system.

Now....how can I improve it?

Well, getting a Sub 3 or two would be my recommendation. Johnny and Samir installed my pair and I have to say I think I have something close to a Quatro. (I'd buy the Quatro's but my space is limited).
BTW, Vandersteen has a new forum on the website. It would be nice to see you there.
Bob

Well you will never experienced listening fatigue with Harbeths but you also may get tired of the homogenization of the sound. Dont know Sonner so would suggest Vandersteens over Harbeth. Harbeth speaker to my ears are very colored and not in the least bit neutral. I deny the viability of the basic premise of lossy cabinets and think they add a huge amount of coloration to any speaker in which they are used. A dead give away that a speaker is flawed is when others say they are best on a particular type of music. 

i would agree w the statement that lossy cabinets a la spendor harbeth et al provides a sympathetic distortion in the mids and midbass, warming up and giving added body to many types of music, and critics are accurate to say there is a level of homogenization that results in the sound character... same can be said of many tube amps, and we certainly love them

nothing wrong with that though -- we are first and foremost pursuing beautiful sounding music that moves us, after all, and 'listenability' is viewed by most appropriately as an asset rather than a liability...

'straight wire with gain' end to end is woefully over rated...