Some drive manufacturters will also claim that disabling the write cache is safer in case of a power failure, but thats a Red Herring. A power failure during a file write is a ticket to disaster, itty-bitty write cache or not. There are several utilities floating around that allow the enabling of the write cache. One of the best and painless is the SCSI Explorer by Adaptec, which is part of their EZ-SCSI package. Free with their controllers.
Error correction takes time.
Remapping takes time. If it doesnt get it the first time around, dont try again. Its just wasting time. Most AV data are contiguous and a prefetch will most likely succeed. The theory behind it is that a flipped bit in a video stream will have much less impact on your well-being than a flipped bit in accounting data.