It depends, like most decisions, on where value for money lies. With smaller lower volume machines, new is the only choice. The new ones are getting cheaper all the time and manufacturers (like Fuji Xerox) often take a punt on low volume situations, by offering a three year warranty. Which they will not do on higher volume machines.
Higher volume machines have also come down in price but there are still big savings to be had by buying second hand, if you can get a late model or even current model second hand machine for half new price you will save thousands of dollars and a service agreement on a second hand unit will probably be the same as on a new one.