As both of you have implied, most of those home warranties are worth the paper they are written on ... but not much more.
Trent,
I think if you use that to "separate myself from some of my competition", that will only work if you imply that warranty is actually quite useful, and, when your clients find out it is pretty much worthless, that "separate myself from some of my competition" could backfire in a negative way.
Nothing like giving out free candy ... until the free candy makes someone sick ... then, look out!