BL 9 vs. Bl 20

I have BL 9, great speaker, 5 stars from What-Hifi and Hifi World. Thoug saw a review of the 20, they also got a superb review. Have anyone heard them both? Any substansiel difference worth upgrading to the 20??

There are mixd opinions on BeoWorld from those who have had both and also those who have tested both.

Some say the BL20s can sound harsher than the BL9s.

Surprisingly my wife prefers the BL20s to the BL18s for her male opera singers.

Some recommend second hand/ life BL9s as better value.

I definitely need to have a couple more auditions before I make up my mind about the Lab 20s. They did sound wonderful when I listened to them, but now that folks have mentioned it, I could gather that they may be slightly harsh at times. My ears have been so accustomed to the smoothness of the 9's now, that I think listening to the 20's would give me the appropriate baseline for assessment.