Nero CDSpeed 3.75 supports 1X/5X/8X/12X and 16X reading speed options for DVD Single Layer discs. We used the same media for all reading speeds, and comparison matrix can be found below:
You can get all the results from the link below. As you can easily notice, the scan speed does affect the reported PI/PIF values. We can say that the 5X and maybe the 8X could be used for fast scanning, since the reported PI/PIF error rates are very close. What is rather strange is the ECC interval of 7ECC blocks. According to some information, we could set the scanning interval from 1ECC up to 8ECC, so results could be compared with LiteON drives (1ECC) or BenQ (8ECC). As currently stands , Nero CDSpeed offers only the 7ECC option.
Below is an example of the PI/PIF scan from the 5X CAV speed: