All these tests are good to identify issues and potential for optimization. But don't forget real world tests with files and workloads that you acutally use.|
Just to give you one example: When I upgraded from the older 3.4 kernels to the mainline kernel 4.0, I ran a few quick tests with Helios LanTest. I found that certain test profiles (I think it was the one for Gigabit LANs) gave horrible values in one direction (something like 3MB/s read speed or so) while the other tests showed the expected values of about 29-30 MB/s (with an USB harddrive attached). Now, that first looked scary, but when I actually transfered files with either Windows Explorer, Finder (on a Mac) or rsync on Linux, I could not reproduce this odd behaviour but saw good readings like 29MB/s for large files and 22MB/s for lots small files instead. At this point I decided to not further dig into it, because it had no practical relevance for me.
So, in addition or before running a series of sophisticated tests, you should test your daily usage and see if you're satisfied with it. This might save you some time.