Digital BW, The Print

Can someone help me out here?

My thinking is as follows. The R1800 might be better, as it has an 
extra ink cartridge, thus making room for the pink cleaning solution to 
prevent clogs. Also, I belive the R1800 has a higher resolution and 1.5 
picolitre drop size compared to the 4 picolitres drop size of the R2200.

Then again, until you actually see the results, you never know. There 
are also factors like clogs, paper feeding issues, etc. to consider. 
This is the sort of information only long-term users can provide. I 
have the opportunity to buy a used R2200 for a great price, but I'm 
wondering if I should wait for a R1800 instead. Keep in mind, this is 
purely for use with Piezo NK7 inks.