I had two ELDX bullets in 6mm, shot from a 6mm Creedmor, expand way too quickly. One was a witnessed shot at 100 yards, lung hit a little high, fall, get up and run away, never to be found again. The 2nd shot, at 275 yards measured, didn't penetrate 4 inches, which was easy to tell when I cleaned it.
So, much as I love the Hornady CX and GMX bullets, the ELDX is not on my list. Hornady makes good stuff, so this may have been an anomaly. But my rule is that if you let me down during hunting season, you get replaced.