I don't think any Marvell based SSD will be able to compete (performance wise) with a SandForce SF22xx based SSD this year. Intel launched the 510 SSD last week which is based on the same Marvell controller, and it performs very similar to the Plextor from what I've seen.
Intel has all but given up on using its own SSD controller, the Intel 3xx (G3) series has been downscaled to entry level, and there are rumours that Intels high end SSD, the 520 series, may well be based on a SandForce SF2281 SSD processor.
There is no doubt about it, the Plextor is expensive, and is certainly outgunned by the Vertex 3 in any likely enterprise usage scenario, but none the less, the Plextor is a very nice desktop SSD, where massive 4K random performance is not a must, and that can be seen in its real world performance, where the tests are exclusively "desktop" PC in nature, and really only falls well behind when you really push the SSD with some heavier than normal multitasking.
Regarding SATA 2
The SSD was on loan, and time didn't permit repeating the tests on SATA2.
Regarding hibernation tests.
That could certainly happen in future reviews, if Intel and Asus can fix these problems in P67. My PC can't do sleep or hibernate with any drive at this time. or to be more accurate, it can sleep, but wont wake.