UNIX and Linux Applications

Hi all,
Just a quick one really; cloning one healthy drive to another healthy drive using ddrescue (was using dd but wanted progress report, have tried various methods but they clash with a nested if statement- long story!)
one drive is 40GB connected internally via IDE, other is 160GB connected via USB to IDE converter cable, not fussed about loosing the extra space on the new drive, just want an exact replica including partition table etc.

so far i tried;
ddrescue -v /dev/hda /dev/sda

which was slow as hell; am now retrying with;
ddrescue -v /dev/hda /dev/sda logfile.log

which i'm yet to see; but what i wanted to know is would i gain any imrovement from playing with the blocksize or clustersize options? And if so, what would be the recommended figures? (both drives are Linux formatted if that helps). Are there any other settings i should know about?

Thanks in advance,
Darren.