IOMeter is another open source synthetic benchmarking tool which is able to simulate the various loads placed on hard drive and solid state drive technology.
We use a custom Kitguru configuration for 4k random write to measure performance. We use the same test, but for random read performance also.
Both drives deliver great results with the 4k random write test, scoring between 55,000 and 58,000 IOPS. The larger 240GB drive scores better with the 4k read test, around 35,000 IOPS.