Digital BW, The Print

My local Sams has dropped the price of the HP 8750xi down to $430.00.
 
I have been saving up money to purchase an Epson 2400; however, at $430.00 I am very tempted to purchase the 8750.  
 
The printer uses three tri color cartridges:  
  Cart 1:  Magenta, Cyan, and Yellow
  Cart 2:  Photo Blue Cartridge with three shades of blue
  Cart 3:  Photo Black Cartridge with three shades of black
 
Having a Tri color Blue cartridge is something that appears to be unique to the HP.  Most everyone else uses light cyan, light magenta, and light black for their secondary color cartrdige.
 
My biggest concerns are the use of multi color ink cartridges instead of single color cartridges and the apparent lack of 3rd party RIP support for HP printers in general.
 
Would any of you be so kind as to offer you thoughts on the 8750 in general and specifically B&W printing with it?
 
Thanks!!!
 
 

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