AS SSD is a great free tool designed just for benching Solid State Drives. It performs an array of sequential read and write tests, as well as random read and write tests with sequential access times over a portion of the drive. AS SSD includes a sub suite of benchmarks with various file pattern algorithms but this is difficult in trying to judge accurate performance figures.
The AS SSD benchmark uses incompressible data to test drives. On the whole the Transcend/ Silicon Motion controller deals with it well, the 4K write performance being particularly strong , however the same can't really be said when it comes to 4K reads.