Digital BW, The Print

That curve was just a random design to illustrate what can be done.

If you are really only going to be using a dedicated inkset for B/W, 
then it doesn't make a lot of sense to buy anything other than QTR or 
maybe IJC/OPM. If you wanted to go into a "normal" CMYK (4K+CMY) 
process for toning images with color profiles in Photoshop, then you 
will of course need a full color RIP.What you buy nw, may need an 
upgrade to work with the next Epson printers, and you can almost bet 
money that the upgrade will not be free. And if B/W is your primary 
interest, the 4800 will do a 5K+CMY configuration if that's how you 
want to run it.