In terms of CD-RWs and CD-Rs, it didn't seem to have any problems reading them and went through them quite easily. There was a slight grainy hissing apparent upon inserting a CD. This also occurred when copying large files. As well, testing the unit with CD Speed generated squeaky sounds, much to the likes of an ill oiled tin man. Not particularly impressive, especially given Samsung's Adopted Acoustic-noise Reduction System (ARS) feature, which is supposed to minimize noise during high-speed rotation. Samsung SC-152L 52X CD-ROM Drive Review @ Neoseeker.com