Digital BW, The Print

I have a 1280 that I use for B&W, using both MIS UT2 and BO/Eboni. I 
also have an R200 that I use with the standard Epson color inks, for 
color.

I was just wondering, is there any reason why I might want to switch to 
the R200 for B&W and revert the 1280 to Epson color?  Obviously the 
1280 can print bigger than letter size and the R200 can't.  But are 
there any compelling reasons to switch, or not to switch--in terms of 
image quality, inkset, or economy?

--Peter