I don’t really know why you would expect other drives not to work, however:
Those original drives are not advanced format drives, all modern drives are. So if you replace with an AF drive you might notice slightly slower write speeds.
I don’t know for sure but I would expect any WD green or WD red 1tb drive to work in there, and my preference would be red. Stay away from 7200rpm drives (WD black etc.) as you’ll probably cook them.