ermmm.. I very strongly recommend not to buy a cheap thing and not from ebay (you don't know where is has been and/or how many times the box has fallen on the ground already. Also, you don't know if the previous owner misused the drive, or even if he is a smoker or not (this will influence the reading and writing a lot and can even damage your CDs, DVDs!))...
A decent new basic DVD writer doesn't cost that much anymore and is certainly not worth the hassle and very uncertainty over ebay...
Lasers are an extremely delicate thing....
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