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 set IOmeter up (as shown above) to test both backup and restore performance on a 100GB partition.
The Drobo 5n isn't a particularly fast NAS but as the IOMeter Backup/Restore tests show its does have high degree of consistency across the different disk groups it was tested with.