I have Z3100, Pro B9180 and B8850 - all great machines, but you can not expect the same result from smaller units due to lack of gloss enhancer, on matt paper there is really small difference in quality.
I prefer to use HP Matte Litho Realistic on smaller units, scrap from rolls, straighten and cut to size. I have APS on Z3100 and use it to make ICC profiles for smaler units, works really great, a lot of people can not tell the differnece when same picture is printed on 9180 and Z3100 - do but it is really minor one.
B&W is excellent on B!
I also use ink from Z to fill cartridges for B models.