Meh.
I got my MX Duo at Staples a month or so ago for $55 out the door, so this a bit on the cool side. If one is patient, I'm sure the MX Duo will show up on sale again soon. I've had both, and not only is the mouse a lot nicer than the Elite, but I actually think the keyboard is slightly upgraded as well - the keys feel different, slight better than the older model.
I'd advise anyone considering this to hold out for another hot deal on the MX to come around. I bought two of them so far and neither time paid more than $60.