Hi Tony, you can read about some of the different printers in the DTG section of the forums here:
http://www.t-shirtforums.com/forumdisplay.php?f=39
http://www.t-shirtforums.com/forumdisplay.php?f=39
Also, somewhere on this site is a spreadsheat that someone created. It was a great tool to use. It gives you a much better R.O.I. than what I did because it factors in the labor, machine cost and other things.