You need to read the datasheet. Many people have been tricked by the "ping-pong" thing.
Here are some times (typical and max)
Page erase and programming time (512-/528-bytes) 17 40 ms
Page programming time (512/528 bytes) 3 6 ms
Page erase time (512/528 bytes) 15 35 ms
Block erase time (4,096/4,224 bytes) 45 100 ms
Sector erase time (131,072/135,168 bytes) 1.6 5 s
So you can ping-pong write a block at typical 17 ms for a block or about 30 KB/sec. Programing time is horrible. 3 ms typical 6 ms max.
If you are streaming to the part you face this:
The erase and the programming of the page are internally self-timed, and should take place in a maximum time of tEP. During this time, the status register and the RDY/BUSY pin will indicate that the part is busy.
So the ping-pong thing does little good. Or as some people say Dataflash is slow as molasses.
Most MTD flash memory devices have a real downside when used for file systems. That's why all popular flash devices for file systems, like SD cards and SSDs, have a block erase/wear controller.
I have not pursued F-RAM since the parts are low density so a file system makes less sense. Dataflash at 32 Mbit is about the minimum density suitable for a file system.