I honestly doubt if it makes much difference.
I did get a Pioneer 36x the other day, the good thing about that was that it is an ATAPI CDROM, so installation is v.easy.
So ATAPI is a good thing to look for.
The extra speed from the Kenwood "True 52X" is a huge leap from what the others offer. Look for UDMA compliance when you buy,as this can significantly up the transfer rate also.
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