You just missed a better buy on the 256 gig Crucial m4 $160.
As much as I love Tom's I do not take much stock in their tier ratings on SSDs.
I prefer the Crucial M4 or the Samsung 830 to the 840. 840 Pro a different story, but much more expensive.
The M4 and the 830 have an outsanding reliability/Least user problems track record.
First, You will NOT see a diff in real life day-2-day performance btween M4, 830 or 840. My primary reason for taking the M4 or 830 over the 840 (none pro) is that the 840 uses a New tri-cell nand I it has NOT been on the market long enoug to determine reliability (Probable great, but is unproven as of yet).
3 M4's (2 x 128 gig and one 256 gig)
3 830's (2 x 128 gig and one 256 gig)
1 840 Pro
2 (UGH) 120 gig Agility IIIs.
Plus a 6 of the older sata II SSDs