Well, a life sentence in a Saudi jail is nothing to take lightly either.
If more countries had them kinds of jails, more folks would probably make an effort to stay our of jail.
As opposed to the "Country Club" kind of jails in civilized countries where people go on vacation for a few months.
The advantage of the Saudi beheading is that it is swift, cheap and efficient.
It is also used quite a bit over there in the sandbox.
A death sentence for adultery or selling moon-shine is overkill (Pun intended) in my opinion, but well deserved for people who murder i cold blood or hijack airplanes.
Also it should be used on those swines that circumcice little girls all over the Middle East and Africa.