Im fond of my plextor 40x for its precise audio extraction and realtime up to speed data transfer, but it also costs an arm and a leg....
so for a cheap CD ROM, I would strongly recommend TEAC... their drives have always been bulletproof for me and you can pick up a new 32x or higher TEAC IDE for like 20-25 bucks.... I have also dealt with Asus, Pioneer/Hi-Val and Samsung and find their drives to be just as good... I havent had great experiences with Sony, Acer, Creative, nor most generic drives.... I mainly stick with the above listed anymore.
I also second that you might as well get a DVD-ROM for the prices out today.... I think that the only of the 4 that I recommend that doesnt make a DVD drive is Teac...
*EDIT* Oh yeah, I quite like Kenwood drives too, great speed... However Ive seen them go out on friends systems, and I dont know that they are necessarily cheap
LoRdAccord