I have seen reviews and tests from both the msachi and RST drivers
, both have claimed to be faster. I guess it depends on the system and settings.
Both are good, there's no clear cut margin of performance that has been verified, so as with most things it's an individual preference.
Some SSD performance threads that I have read tend to have more RST drivers but, that doesn't mean much at the end of the day.
You can install the RST/msachi drivers at any time, the only problem comes when your BIOS is set to IDE and you install the RST/msachi drivers, then your system will crash.
You can change from IDE to AHCI/RAID in BIOS and install the corresponding drivers without re-installing the OS.
It will work on some systems by installing the AHCI/RAID drivers, reboot into BIOS and change the setting from IDE to AHCI/RAID, reboot. If this doesn't work there is a registry setting you can change.
Here's a tutorial: AHCI: Enable in Windows 7 after OS install
You should make a restore point and/or image backup before trying these methods.
@ Layback Bear, that's your SSD driver
The controller driver in Device Manager is under 'IDE ATA/ATAPI controllers', usually the first listing.