Well from what I’ve seen personally and other people have said as well the 1640 wasn’t a real good CD burner, not evil like alot of LiteOns though. The 1650 was an improvement although there are better CD burners. As far as scanning I’d rate my drives in this order(from 1st to last) 1640,1650,1620. There’s not much of a drop off between my 1640 and 1650, my 1620s don’t seem to be as good for DVD scanning though. None of them are bad scanners, but I’ll continue to stick to my 1640 for scanning until it dies or something replaces it.