Digital BW, The Print

I currently am using piezography inks.
I am having problems with muddy prints and am in the stage of giving 
up.

I have an Epson 1280 and really need to move to something different.
I like being able to print to fine art paper and the quality I had 
been promised with piezo.

Can anyone make any recommendations as to which print ink set to try 
next.

Thanks
AW