Benchmarks: Atto Disk Benchmark
Atto Disk Benchmark's read test pushed the Agility 4 to 421MB/s, which is in line with OCZ's claimed rate of 420MB/s. The v4 reached 277MB/s, exceeding the 230MB/s cited by Crucial.
The Agility 4 reached 410MB/s when working with 32K data and maintained it through the 128K test, and this is the exact figure OCZ says the drive is capable of when writing. The v4 reached 212MB/s, a tad higher than its supposed 190MB/s limit and much slower than the Agility 4.