I haven't listened to a Lavardin in close to a decade but it was an unusually copasetic solid state/Zu pairing when I last auditioned both in my own house. Lavardin has made some updates to their circuits so based on the first years of hearing their updates yield real sonic improvements, I have confidence the current generation are better still.
Into the Zu Superfly 16ohms load, the Lavardin will likely sound sweetest and cleanest driving that impedance, compared to 8 ohms or 4 ohms, though any difference you perceive won't be vast. But for the 50 and 55w/8ohms rated models, Superfly will cut the output to 25-30w, with decent dynamic headroom. That will be fine in most normal size domestic rooms, but if you have a large room or just want some added dynamic elasticity, you can from Zu 25 ohms/10w resistors to run across the speaker inputs to yield a load just under 10 ohms, to get back most of the 8 ohms-rated power back.
Lavardin has a US distributor again, so good luck. If you're specifically seeking a solid state amp for Zu instead of tube, and want to consider alternatives, I can suggest others if I know what you are hoping to pay.