The best DVD-Roms are made by Toshiba. At rpc1.org, there are hacked firmwares available which allow ripping of CSS-protected discs @10x max. In addition, DVD- and DVD+ can be read at full speed (burning quality needs to be good). My recommendation is SD-M 1712. If it is no longer available, go for a SD-M 1802.
Toshiba DVD-Roms are more quiet than LiteOn and have much lower seektimes. Very nice drives.