Using the following two drives here and don't really notice any difference when reading CDs:
Sony CD-RW CRX320E: 52x32x52x CD-RW / 16x DVD-ROM

Sony DVD-RW DW-D22A: 16x4x16x DVD+RW / 8x4x16x DVD-RW / 2.4x DVD+R DL / 48x24x48x CD-RW