CrystalDiskMark is a synthetic benchmark that tests both sequential and random small and mid-sized file transfers using incompressible data. It provides a quick look at best and worst case scenarios with regard to SSD performance, best case being larger sequential transfers and worse case being small, random transfers.
The OCZ Vertex 4 drives offer some of the best small file performance we have seen in CrystalDiskMark. And the Vertex 4 drives simply crush everything else in the 4K / QD32 test. Sequential reads are much better here, but still trail the SandForce drives. However, write performance remains very strong.