Digital BW, The Print

Does anybody in the forum have any experience with  Lyson's Quad 
Black inks used on a Canon i965 printer? I have just begun doing 
some experiments on Lyson Papers, and the results have not been 
fantastic. The prints I have done sofar are flat, regardless of all 
the changes tried with image mode, printing space, printer driver 
settings, black only printing, printing either with or without 
Lyson's profiles, etc. I tried all settings suggested in the Lyson 
web site, without reaching the richness of a demo B&W print Marrutt 
kindly sent me. I noticed today in the printer dialog box that, 
after printing about 50 B&W prints, the "photo cyan" and the "photo 
magenta" gray cartridges are almost empty, whereas the other 3 gray 
cartridges + the black cartridge are almost full. This may explain 
why my prints are all flat, with the exeption of a couple of high 
key pictures.
Thank you.
Antonio