You can make a very rational argument to your wife ...
Unless the Mrs. is a CPA, that'll likely be the wrong way to go. Women, by and large, don't make purchasing decisions based on analytical facts and figures - they base it on emotion 9 times outta 10.
"Do you remember how
surprised we were when we heard that car? How
shocked you were that it wasn't a live band. How
good is it going to
feel knowing that we'll have a great system like that? You'll be the
envy of your friends every time they come over."