Digital BW, The Print

I wonder whether anyone on this list has used these inks?
I have downloaded an ICC profile for my Epson 870 but I
have not found one for my Epson 800 (4 channel printer)
for which I've now got the 2 quad-black cartridges. Previously
I used Lyson's Small Gamut inks in the 800, with reasonable results,
but some of the prints changed colour almost as badly as the OEM INk
on the Epson 870. I would be grateful to hear what experiences others
have had, with the Quad Black inks especially.
Thanks in advance!
Serena Wadham.