Your speeds seem pretty normal (for OpenBSD), I dare say.
Code:
time cp test.img /mnt/
2m11.16s real 0m00.00s user 0m01.84s system
That's a 260M image file of random data copied to a FAT32 formatted (
newfs_msdos(8)) USB stick attached to a USB
2.0 capable controller on my ten year old laptop. Took 131.16 seconds to copy. You'll just have to live with it.