QTR-Quadtone RIP

I'm in the process of upgrading from my 1160s and piezography to a 2200 and QTR. I've 
made several prints with the 2200, QTR and the UC inks delivered with the machine (I did 
replace the Photo black with Epson Matte black.) and need to think about buying more ink.

For grayscale printing, with warmish toned inks on matte paper, would I see better results 
with Epson UC inks or the MIS UT7 inks? For me "better" means smooth tonal transitions, 
with deeper blacks and dot-less highlights secondary concerns, but I welcome other 
definitions.

(Ignore that the UC inks allow printing color.)

Michael