Color printers

Looking to replace our problematic HP Color LaserJet 8550gn.

Our marketing department uses the printer to do some small volume pre-press
proofs and they can be very picky about the color output of a printer. It's
also used for printing PowerPoint presentations. Although we have several
LaserJet 4600s, users don't like the color output of the 4600 as much as the
8550.  But the 8550 is slow and prone to jamming. 

As a replacement we looking at the HP 5550, XEROX Phaser 7300, and XEROX
Phaser 7750.  The printer must support tabloid size printing.  Does anyone
have any experience with any of these?  Someone suggested we look at an
Epson 5000 ink jet printer with a RIP.  That seems to be a whole different
technology that I don't know much about. What would be the advantage of an
inkjet printer over a laser printer besides less initial cost?
 
 Midi or upper four figures is our expectation for a price to replace the
printer.  Any opinions out there?

    
Bryan Burns
System Operator
ECHO, Inc.
Lake Zurich, Illinois