I built a new machine for my office and used an OCZ Agility SSD for the boot drive. It runs fine but doesn't boot any faster than my home machine with WD 750 Black hard drive. In reading the latest articles on Tom's homepage I got the idea that maybe I need special settings in the BIOS to make the drive run at its best. This machine has Win7-64 and an i5-750 with Gigabyte GA-P55-UD3R motherboard.
Ahci does make a huge difference, both with SSD and with Sata/6000 Hdd. They say Seven has its own good Ahci drivers.
The Agility was not the best choice. Their older Vertex is clearly faster. Pity for you. An Ssd is difficult to chose; read a lot, compare the controllers (Indilinx, Intel, Samsung), don't rely on contiguous read and write speed.