PCD inserts comprise a PCD body having multiple FG-PCD regions with decreasing diamond content moving from a body outer surface to a metallic substrate. The diamond content changes in gradient fashion by changing metal binder content. A region adjacent the outer surface comprises 5 to 20 percent by weight metal binder, and a region remote from the surface comprises 15 to 40 percent by weight metal binder. One or more transition regions are interposed between the PCD body and substrate. The transition region comprises PCD, binder metal, and a carbide, comprises a metal binder content less than that present in the PCD body region positioned next to it.