Use HDDerase 3.3 and ONLY use option 1, the option you selected will fragment the HELL out of your drives.
Did you put mobo in IDE compatible mode?
Unplug all your drives, you should wait until JUST after you load hdderase.exe before you plug in your x25-m. This should allow you to select option 1.
Your results are too bad to be anything to do with alignment and is a wild goose chase as alignment mainly affects small writes, so it must be due to fragmentation.
I'm pretty confident if you do the above performance will be fine.