I had brand new discs (and presumably pads) at the front of my AUC, while the rears look distinctly like they'll need replacing in about 5k miles. So the 5k miles sounds about right.
For the discs, not without taking the wheel off (afaik). I tend to eyeball it based on corrosion, how thick it appears to be and the like - far from a proper check I'll grant you that! More info: http://www.ehow.com/how_7279634_check-brake-pads-wear.html