Titan, I think what you suggest will give the most accurate results. When I run the test I also thought about reflashing it, but I didn't want to lose my installation. So I ran 'top' to see if there were any busy processes first.

I did run tracker-processes -k

I've remembered now from my previous tests on a flash card a while ago that formating FAT32 to a cluster size of 32KB significantly improved performance. I think most flash cards and USB sticks are formatted to this (though I'm not sure how to see the parameters on the N900). ext 2 & 3 only support a maximum of 4KB per cluster (8 sectors).

I think ext3 journalling has an effect on writes only.

When you did your write testing, what parameters did you use?