I use my walking foot for about 90% of my sewing, and find it especially important for machine-applied binding. However, it is difficult to line up for close-to-edge quilting under the wide foot. Here's how I solved the dilemma and kept the advantage of the foot evenly moving all those layers of fabric and I get a hair's breadth near the folded edge of the binding:
Align all layers of fabric beneath the wide foot which ensures that not only both under feed dogs will get a good "grab" on the fabric, but so will the dogs on the walking foot. However, that leaves the needle not very close to the folded edge of the binding. So, simply adjust your needle to the side (width adjustment) and keep the folded edge lined up with the left-most edge of the walking foot. Works every time for me.
Hope this helps.