Any Nike + users use for running? Good/Bad?

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I just bought a pair of Nike (Nike+ ready) running shoes. My first running shoes, actually :). Anyway, I am curious about the little nano pod that can be bought and added to the shoes. I am wondering if anyone here uses/used the pod/shoe combination and liked it or thought it was a waste.. etc.

I looked around on the Nike site and the pod itself isn't too bad at $29. My question here is; is it just another one of those "cool" things you bought to try out or thought you had to have the latest and greatest when you got into running? Or was it really neat and helpful with tracking your runs, your speed, etc?