I grew up with a McIntosh A/D/S combination in a large room. Since 1998 a few brands I've owned are Totem, B&W, Verity, Devore, Fyne, Zu, Klipsch.
I thought the Zu Union was fast and fun. It didn't have the clarity I wanted but as it broke in it developed, as did the bass. In the end I found them bit lean.
To be fair I didn't use tubes with them, but class A Luxman. Perhaps this would have done it for me but the detail still wasn't there. They were full with "loudness" engaged, which I never used with most others.
They were fast and found them very engaging (not bright) and fun to listen to. I wouldn't sell this speaker short, but as always- based on your budget and preferences.
