Digital BW, The Print

I need some help with printer specs for B&W printing. From this list, it
seems that people are getting good results using a variety of printers. The
4000 and 2200 seem to be considered the current big guns.

When I look at the Epson Specs(reference at the bottom), the R800 has the
highest resolution and the smallest droplet print head. It would seem to me
that the R800 would provide the smoothest gradations and the finest
patterns.

I am sure there is more to fine B&W printing than the specs would indicate.
If black only works well I would be most interested as it would seem easier,
but I am not opposed to multi-ink configurations.

Could someone explain what I should be looking for or direct me to a proper
website?

Thanks so much

4000
17inch
7-color individual ink cartridges
2880 x 1440 dpi resolution
3.5-picoliter ink droplets

2200
13inch
7-color individual ink cartridges
2880 x 1440 dpi resolution
4-picoliter ink droplets

R800
8inch
8-color individual ink cartridges
5760 x 1440 dpi resolution
1.5-picoliter ink droplets

1280
13inch
6-color 2 ink cartridges
2880 x 720 dpi resolution
4-picoliter ink droplets