Re which consumes more power -- SRAM or FLASH -- that's an interesting one. If you take two devuces created at the same process node -- say 65nm, then the SRAM will consume more power. But the FLASH devices are typically 1 to 2 process nodes behind. So most Flash devuces today are at 65nm or higher, whil estate-of-the-art SRAM devuces are at 28nm. In this case, for the same number of gates, the SRAM will consume less power I think.