Alright, I had to do some research as I wasn't too familiar with the Force GT drives, those are the latest drives on the block.
Both the Agility 3 and Force Series 3 drives utilize asynchronous NAND, while both the Vertex 3 and Force 3 GT drives both use the faster, but slightly more expensive synchronous NAND. So both drives you're looking at are identical in base hardware. To the best of my knowledge Corsair uses the SandForce firmware releases, while OCZ may be tweaking its own firmware. This hasn't ever been confirmed as much as assumed due to OCZ's past history and constant use of its own custom PCB designs.
The warranties are the same, so honestly I'd go with the cheaper drive, the V3, but that's because I don't mind rebates. If we are talking about the price of the Force GT, I would instead recommend this one
http://www.newegg.com/Product/Product.aspx?Item=N82E16820227714
The 120GB V3 and 120GB V3 MI have a larger performance difference than that seen in my review of the 240GB drives... I attempted to explain it on the
first/last page of my review, but in a nutshell the 120GB V3 MI is easily worth $10 over the Force GT. If you plan to use this SSD and never upgrade it for the next five years, or you don't plan to use the MIR at all, then I'd say just spring the $30 difference and get the V3 MI over the base V3.
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As for the reviews and problems in general... it does seem there are issues going around. The first negative review I read the user mentioned a Marvell controller... as Rob can personally now attest himself, I strongly advise against buying a SATA 6Gbps drive for a Marvell (or even Jmicron) controlled port. The driver has problems and the performance is so bad a user is better off with an Intel SATA 3Gbps port.
I understand there are genuine users with genuinely serious problems with SSDs, but there always have been. If there's a specific, single issue with a product that'd be something else, but so far nothing has been shown regarding any of the three drives mentioned. I'd personally use any one of them in my system. (in fact, I already do.)
Now, back to Marvell. I just did these tests a few days ago when Rob, I, and Dave were hashing out some performance issues he noticed on HIS X58 motherboard. ALL of these tests are on 6Gbps ports using a 240GB Vertex 3 Max IOPs (the X58A test is a normal V3, but shouldn't matter here)
P8P67 Marvel:
http://bit.ly/oWmbNK
X58A Marvel:
http://bit.ly/o5K8Zq
P8P67
Intel port http://bit.ly/qBVfvM