First of all, the device is guaranteed to retain memory even if it is not on for at least 10 years at 85°C. Also, the same value can be written over 10^15 times in memory and it will still dependably return the same result. This is over 1 billion times more write cycles than Flash or EEPROM. Also, if a different bit is written in that memory just one time, the entire endurance cycle starts over. A point to note is the fact that TI has been making and selling FRAM with Ramtron for over 10 years. It is in automotive and other harsh environments around the world, and it is doing well.