Kodak Pro Back 645M any opinions??

First I must apologize for posting this question in a large format forum but I c an't seem to find any info about the digital back in question other than adverti sements. I have been asked to look into the Kodak Pro Back 645m and would like t o know if anyone is using this equipment and what their unbiased opinion is abou t the back. I will be using it for garden images so the fact that it can be used un-tethered to a computer out in the field is quite appealing. Any info would b e greatly appreciated, thanks.