Digital BW, The Print

Hi, 
  There are basicly two options: 
Either 
1- the HP photosmart 7760, 7770, 7790 with a dedicated gray ink 
cartradge. 
  Drawback: it only prints upto letter size. 
Or 
2- Epson 1280 or 1160 using MIS inksets solely for B&W to avoid 
color cast on B&W prints. 
  Advantage: it provides larger print sizes. 
  Drawback: more expensive. Is my understanding correct that one has 
no choice but to buy some additional software to use MIS inksets 
with these printers?  
  I see some softwares on MIS webpage that run under windows and are 
quite expensive such as R9 Driver. I am also a linux user and i know 
that there is a software under linux: QuadtoneRIP. However there is 
no guarantee that i can successfully use this software. So far, it 
seems i have installed it but i don´t see any such option under 
webmin or webcubs 
printer set-up utilities of webmin or webcubs. So not quite sure if 
i can use the printer under linux for B&W. 
  MIS webpage is not quite clear to me on what i should buy? Are the 
cartridges they are selling filled with ink or i have to buy  a 
cartridge and an inkset separately?  
ON MIS homepage, I have seen products with codes: 
ARC-T007-UTK 
ARC-T007-QVM 
ARC-T007-QFS 
ARC-T009-UT2. 
 I am not sure which one is the right choice? 
 
Are there other ways to print color-cast-free B&W prints? 
Also, i can not find any dealer on line selling epson 1160 (seems 
less expensive than 1280). Do you know if this printer can be found 
around for sale? 
 
Regards, Ramin