I am under the impression that NP0/C0G ceramics are Class 1 MLCC's. Is that not correct?
NP0/C0G is a certain material, well suitet for audio because it's not causing much more distortions then the best film caps.
MLCC is a way to build a capacitor with higher capacitance by using several layers of any ceramic material.
So if you can find an MLCC made of NP0/C0G you're fine. I mentioned earlier how to verify that it's NP0/C0G.
@Klaus: you know I mostly try to use simple language, but in this topic from the headline on it's more of a technical, "DIY" thing.
Demystification of very common capacitor myths might be interesting for less technically oriented people too.
At least you get one explanation why different caps sound different.
I have learned enough going through Cyril Bateman's findings to make me curious to dig deeper.