I have always been told that to be able to use CD a more than once you have to get CD-RW's. but on the computer I have now it can overwrite CD-R's. is this strange or is there something that computer makers are putting in the newer comp. to make them do this? is there any drawbacks to doing this, like maybe it doesn't write to the CD-R as well as it would if I used a blank CD-R or CD-RW?