After having had the ditton 8, then 44, I am very happy with the result! Voices are very well made, low round and very dynamic (as long as the amp is powerful enough!)
I do not understand Quon has done as much custard around 44 while the 551 is lighter and much better in the medium! and more stress because of a tweeter (as in hf2000 44.66 ...) everything is fused and pots not bad influence on her short, more versatile and more powerful than the 44 for me they are terrible!
I am eager to go 66/88!

mounted on Nad 3155 60w
Yakin then Vk-2100 Custom (hybrid lamp / transistor) 80W