ObidiahSlope: Alan it seems you are working in graphic design environment.
I suggest you need to spend some time and determine whether or not you require a Post Script capable printer.
Colour shifting can be a real headache with some printers. You may need to create a test document with the printers colour profile and do a test print to see if the printer you are considering is prone colour shift.
Thanks for your comment - clearly you know way more about this than me!
We aren't a graphic design company if that is what you mean - these are just our in-house product catalogues that we give out to customers, and they change a lot, so we print on demand to keep a small stock on the counter (five to ten copies).
Having said that, I don't really understand what you mean by 'colour shift', except that I might guess you mean where the blue (for example) output from two different printers is not exactly the same shade?
If so, we aren't too concerned - it wouldn't really matter too much if the blue on one catalogue was slightly different to another catalogue, as long as it was fairly consistent throughout a single document.
If I have missed the point, please do let me know!