Does this sounds familiar to anyone? brakes are quiet and work fine while slowing from speed all the way until the final few feet at really low speeds before being stopped.
If brakes are otherwise in good condition, here's what I would try..... 'bedding' them in a little bit. Find somewhat deserted road, get up to ~50, then hard brake to ~20, then repeat a few times. This will normally help seat the pads and/or clean crud off of them.
Check all the caliper pins. They can get rusted and stuck but from the outside they look ok. Remove the calipers and make sure they slide free and grease them with brake lube.