The problem is with your OCZ Agility 3 drives that use asynchronous Nand.
AS SSD uses incompressible data and this test provides worst case results with asynchronous Nand ssd's.
There are many AS SSD web benchmarks that show that asynchronous ssd's have noticeably lower scores.
Don't get hung up on the sequential read/write scores, the small file 4K scores are much more important.
Keep in mind that newer synchronous and toggle Nand drives have significantly higher IOPS scores and are much faster.
The Intel sata3 ports will provide better performance than the Marvell (GSATA3 6~9) ports.
Some links that will provide more information:
- How does my RAID0 look?
- HARDOCP - Introduction - NAND Flash Faces Off - Synchronous vs. Asynchronous
- OCZ Technology Agility 3 240GB SSD Review - PCMark Vantage - Drives with Data Testing
- TweakTown's SSD Fill Testing Explained
- Asynchronous vs. Synchronous NAND Flash SSD Performance
- AnandTech | OCZ Agility 3 (240GB) Review