I am running one 831 head in my l25500 and all is working well at the moment, I changed the chip and need to remove the oem ink (Lc + Lm) so I could get the right one for my system ( cyan + Lc) , the Lc is perfect but the cyan is a little ruff, I hope to try to change the system over to all 831 inks after sorting out the chip and hope it will work better with the right ink, I will keep you updated