When we install brick edging we install the bed first. If it's going into an area with existing lawn this is perfect. We cut the bed edge with a sod cutter or bed edger. Prepare the bed, plant it, etc. Then we rake/shovel the base area along the grass line for the brick edge. Use a little screening or sand (1" ish) so it's easy to trowel. Install the brick and sweep sand in the joints. We then rake the soil to the back edge of the brick from the bed and then finish rake. The lawn acts as your guide for the brick edge. We have not used brick edge, I can see where this would be helpful. But we haven't had too much movement in the past. As well, I don't like using an edger on brick with plastic brick edging. So I'd rather not install it for that reason. Seems like equal pressure on both sides of the brick edging - so not much is pushing the edging in or out.