Let me backtrack - I just looked and you did not specifiy which MB/CPU you were using.
(1) It is not a question about SSD brand, it's about the controller that the SSD usies, In your case, and mine (a Pheonix PRO on Gigabyte P55-UD4P MB), it is a sandforce 1200 and the southbridge on your MB.
What I should have verified (and what you should have identified) - is your system using a Intel chipset (ie x55 or x58) or is it based on AMD.
If AMD, Need to verify if AMD has finally put out an ahci driver that works with TRIM. Otherwise use the default microsoft default AHCI driver. (Forget intel drivers).
If your system is based on the intel platform, follow what I said in my previous post.
Added
There are a couple of previous post on this subject. In terms of performance If you run the AS SSD bench mark, I think you will find your overall score to be very low, about 1/2 of what it should be. My score using pcide = 231. Reinstalled. using iaStor overall score = 471 which is very close to manuf stated performance.