Good question ! Seems that the PRO is faster, has higher life span (but i don't plan on keeping em 10 years anyway) but it's also older. EVO is newer, should be at least as reliable and has the rapid mode which should make it even faster (using RAM ?). There's a 30$ price tag diff in favor of the EVO atm on newegg. Memory thing website doesn't have the 256 pro, just the EVO at 199CA$. What would u pick and why ?
EVO and PRO both have the "rapid mode" you speak of. And yes it uses RAM. You set aside a specific amount of memory that is used as a cache for the drive to speed things up even more. Solid state drives are 10-200x faster than a mechanical hard drive, system ram is 100-10000x faster than solid state drives. The EVO is a very good drive, but it has much higher write latency penalty than the PRO if you do not let the drive have a good amount of idle time in which to trim the memory cells. For most people in most situations the TLC memory in the EVO will be fine still. The EVO will also slow down in speed a good bit when its cache space runs out, as most drives do. The PRO though will maintain a faster speed overall compared to the EVO when both are not reading/writing from cache.