Slow Built-in Memory?

[Exempli Gratia]

Is the built-in ROM memory supposed to be slow? It seems to be compared to the RAM, and even my SD card (Lexar). I've been storing My Documents on the Built-In for the power-loss protection, but may have to reconsider.

Are there any formal benchmarks on the types on memory, and/or explanation/recomendation for the use of each?

Thanks,
e.g.

[Howard2k]

I benchmarked the memory types on my X5 when I first got it and it certainly was slower than both SD and Main Memory.

Originally posted by Howard2k
I benchmarked the memory types on my X5 when I first got it and it certainly was slower than both SD and Main Memory.

How did you do that?

Flash ROM is slower than RAM (SDRAM).