I have not shot the same bullet you’re speaking of but I have had some potentially applicable experiences. I shot a lot hogs with a .222Rem and a Lapua 55gr soft point. It would penetrate a good 24+ inches and killed hogs quite well with lung shots. One day I tried it with a 223AI, and after shooting the hog three times, I discovered that they had blown up so violently that they made wounds about the size of a grapefruit starting just under the skin. I shot a bobcat with the same setup, and it completely removed his chest. A .222Rem with a 50gr BalisticTip is a lot better for hides. So....with a really frangible bullet, it can be very effective at low impact velocities and borderline worthless at high impact velocities.
On the other hand, a really tough bullet and a low impact velocity can end up doing little more to an animal than an FMJ would. I watched my dad shoot a mule deer three times in the lungs with a 168gr Accubond from a .308Win. The exit holes were a little larger than the entrance. The damage in the lungs was nothing spectacular. That’s still better than blowing up shallow, because A) you have a chance of reaching vitals, and B) you have a better blood trail. It’s also easier to manage. If you have a cartridge with enough muzzle velocity to make the tough bullet perform properly, then management comes down limiting your range. With the very frangible bullet you would literally only shoot at thing beyond a certain range, which is a bit of a ludicrous way to go about it in my opinion.
Most hunting bullets are built with tougher jackets than their match or Varmint counterparts. Some are tougher than others. Most people I notice who really like Accubonds appear to be shooting them at fairly high velocities. My dad’s .308Win load was not moving very fast at all. Then there are a few outliers. The Partition, A-Frame, Dual-Core, and possibly a few others attempt to work well under a broader range of conditions by using a very frangible front section that will expand even at very low velocities, and a very tough rear section that will penetrate deeply even at very high velocities. There is also the Berger VLD, which was not designed for use on game, but once they were shown an awful lot of film clips of it being used on game, they started testing it. It generally penetrates 2-5” before it starts coming apart, and when it comes apart the wound is deep and wide, they also appear to work well at both very high and very low impact velocities. I have not had any negative results from using them, but they do have some of the qualities that people associate with bullets that are too frangible to hunt with.
ELD-X? I don’t know, but I would be leery of using a bullet on game if the manufacturer did not, which is why I never would have tried a VLD before Berger did a lot of testing with them.
If you’re worried about bullet performance and want piece of mind, I can’t imagine a reason to worry about a Partition.