I've never seen a 1610 so this is just speculation on my part.
Is there a label that shows the complete model # and manufature place and date and the firmware installed?
Using dvdidentifier, cd-speed or whatever does the firmware match what is on the label to what is really installed?
What I would wonder is that a rma'd drive that some one crossflashed and got sent back out for sale?
The only thing that would concern me is if I paid for a new drive and got a returned drive instead. OR they sent a retail drive in place of an OEM drive, that be cool!