I got my Lampi back from Lukasz a few days ago and wanted to share some thoughts with you.
I have one of the new Amber DACs fully featured (with DSD and Jupiter Caps, DHT rectifier and chokes)
FYI, my system contains of a Windows 8 machine, Gryphon Diablo, MBL 116, Aqvox USB and Nanotec 777/207 cabling.
I had two DACs for comparision, an Electrocompaniet ECD2 and a Lector Digitube S192 (yes, the one with the dreadful measurements - I sold it already)
To make it short: The Lampi bested both of them by a quite big margin.
I don't want to repeat what others have already written, but in my opinion the standout quality of the Lampi is the air around instruments it reproduces.
It manages to sound heavy on tones, yet at the same time light around them, I have never heard a converter that did both.
DSD is of course the pearl of the DAC. I'm going to convert all my flacs to DSD in the next months or use JRiver on-the-fly, I have to compare these two in the next days.
All in all, the Lampi stays and I'm really happy with it.
I don't know how Lv4 compares to the Amber, for now I'm more than satisfied.
Christoph