HDTune tests a similar level of features that HDTach does, but with a slightly different access pattern and thus can provide us with an additional set of benchmark numbers to compare between storage configurations. Here we can get the minimum, maximum and average transfer rates as well as the burst rates and access times. CPU utilization has proven negligible with modern processing horsepower, and is no longer included.
The RE is yet another step improvement over the Red, and comes close to the VRaptor yet again.
Peak transfer rates came within a percent of WD's stated 181 MB/sec claim.
Random access times were respectable, with only slightly longer latency over the previous generation. This is likely attributed to the heavier head pack assembly and/or more conservative tuning.