Digital BW, The Print

Hi all, 

I'm kind of new to digital b+w printing, I'm using at the moment a 
1290 (1280 on foreign markets) with only black ink.
I'm getting pretty decent results, even though I know that this way I 
get only 256 shades of gray and no smooth tonal passages.

I'm thinking about buying an old 1200 or a 1160, for b+w printing 
only, but I really wouldn't know what inkset to buy.

It seems to me that piezography would be the best (although I'm not 
sure) but it's definetly too expensive for me.

Which system would you suggest and coupled with which printer? MIS or 
Lyson?

Thanks, any help would be really appreciated.

Paolo Valentini