do your self a favor and buy one directly from pro digital. they have used dats and you can rest assured it will be fully functional
his prices are reaonable, the piece of mind is worth it alone.
or you can buy one off ebay, hope it works, and then eventually send it to pro-digital for a tune up anyway
here is a link to the site and his used gear list
http://www.prodigitalinc.com/ click the used gear link 1/2 way down the page on the left, and when you call ask for paul
good luck