i quote this from a website
it tells you how long your SSD should last
"To help users estimate how long an SSD will last, SSD vendors such as OCZ have come up with formula: a drive's life span equals its capacity multiplied by its write endurance rating, divided by the average daily writes. For example, the 120GB Vertex 3 SSD has a write endurance rating of 3,000 cycles. If you write 50GB on the drive daily, the total number of days the drive will last before becoming unreliable is: (120 x 3,000)/50 = 7,200 days, which is about 20 years. If you write an average of 100GB a day, the drive would last about 10 years."