Digital BW, The Print

I've been using Epson Photo Black and Epson Enhanced Matte paper in 
my 2200 for BO printing just to see what BO looked like. I've been 
generally pleased with the results but the prints are on the warm 
side so I replaced the Photo Black with MIS Eboni which everyone 
seems to say is the best black to use for BO. I ran three cleaning 
cycles  and then printed. The prints are still on the warm side and 
don't otherwise look any different than the same prints done with 
Photo Black. Is it possible that three cleaning cycles weren't enough 
to remove all the Photo Black from the printer? Apart from that, what 
am I supposed to be seeing with MIS Eboni that makes it preferable to 
Epson's Photo Black for BO printing?