From the AN website:
"The Audio Note (UK) KAISEI range has been
developed over the past years in collaboration with the engineering team
at Rubycon (of Black Gate fame). Whilst working on our top of the line
Black Gate replacements (which we should releasing toward end of the
second half of 2016) we realised that it would be possible to put
together a range of more affordable electrolytic capacitors that use all
of the same materials as these supreme components (the same special
electrolyte, foil and construction quality) apart from the hyper
expensive and extremely difficult to produce Graphite impregnated paper,
so the only difference between the KAISEI capacitors and the
forthcoming Black Gate replacements is that the paper is not graphite
impregnated in the KAISEI, otherwise they are the same."
I tried them in high capacitance values as coupling caps, bypassed by ClarityCap MR film caps, in Pass ACA 1.2 kit Class A monoblocks. They sound fine after a long break-in cycle.