I just installed 170b4. After ripping, it will not eject the disk (as specified in settings) unless "Use Native NT SCSI Library" is selected. (In 151, CDEX wouldn't run at all unless the SCSI library was selected.) Windows 7-32, Asus DVD-RW (http://www.newegg.com/Product/Product.aspx?Item=N82E16827135204&Tpk=27-135-204)
It's not a big problem, I just thought you might like to know about it.