Is it upgrade from SF auditor to Harbeth SHL5 plus?

I have had a pair of Sonus Faber auditors (not M) for over five years. I am happy with them but "upgrade bug" is calling me, I would like to have something with better high/low extension, and over all bigger scale. I am very interested in harbeth shl5 plus. I wonder if they are a good upgrade. Thank you very much!
I am familiar with both speakers, which, IMO are both excellent.  The SHL 5s do have a "bigger" sound IMO, but unfortunately, without a home demo, there is no way to predict which one will sound better in your listening room.  In the right room, the SHL5s can have a huge expansive sound, but choked in other rooms.  My advice is to see what you can do about getting a home demo if possible.  If buying used, I would not sell the SF until I had a chance to A/B both in the actual room they will be used.  You can always turn Harbeths over without much of a loss when you buy used.  I really love the SHL5 and I hope they work out for you.  
chayro, thank you very much! Home audition is not possible. I will take your advice to keep auditor and do A/B test in my room. 

There is not much of a class difference going from what you have to a Harbeth. 

if you want to get more extension look for a suitable floor stander and one with more advanced driver technology. 

It will come down to budget and room size and matching gear. 

We just had a client trade in a pair of Sonus Faber Cremonas to the new Paradigm Persona 3F as he also wanted greater  clarity, and he is very happy.

Dave and Troy
Audio Doctor