I just pulled 8 HUA721010KLA330 1TB drives from a RAID 5 because I'm upgrading to 2TB drives. I tested the file benchmark using HD Tune Pro. The read and write speeds range greatly from these identical drives. Write speeds range from 40MB/s to 80MB/s. Read speeds range from 10MB/s to 80 MB/s. I'm worried about the drives that have read speeds of 10MB/s and write speeds of 40+MB/s. Why such a difference in read and write speeds on the same drive? Why is the read speed so low? Crystaldiskinfo reports all drives are in good health. Hard drives are about 6 years old. Should I have done a normal format instead of a quick format before reusing them?