AS SSD is a benchmark that uses non-compressible and completely random data. What this means is that the drives using the SF-2281 controller cannot compress the data first, which takes away one of the strong advantages of this controller. Therefore this is a useful benchmark because drives that use the SF-2281 don't gain an upper hand.
The shortcomings of using asynchronous NAND memory is apparent here. The SSD320’s sequential read performance wasn’t even half that of the SSD720 and the other high-end SandForce drives. Looking at the more intensive 4k and 4k, 64 threads work loads, while the Transcend SSD320 posted pretty competitive write performance figures, its read performance was significantly slower than the SSD720 by around 25%. Finally, in the simulated copy benchmarks, the SSD320 was around 40% slower than the SSD720 and the other high-end SSDs.