Will my use be basically for SO(windowns 7) and software. which SSD should use?
If you buy today, you will suffer buyer's remorse in the fall when the new gen3 SSD drives arrive.
Using a smaller NAND manufacturing technology, they will be bigger, cheaper, and faster.
I would get the INTEL SSD today for a couple of reasons.
1) It is a cheaper investment today.
2) It's performance is about the same as the vertex and relatively consistent for all type of work.
3) At resale time, I think you will get more back for the Intel brand.