It all depends on what you want.The cloning results in a fully operational drive without having to use a boot disc to restore the data on it to a working state.
Obviously since it seems Acronis needs a wiped drive to clone to, Norton Ghost would be the way to go if one elects to use cloning, as it will overwrite the target drive.
If one elects imaging, I guess it wouldn't matter, but I'm hard pressed to see why anyone would use imaging if they are going to use two hard drives.
I believe we've beat this horse to death, and it's getting very redundant, making the same points over and over.
It's all explained here:
http://www.ctpc.org/nltr1007/ae1007.htm