In my experience with 175 ELDX - Bears, Deer and elk out of a 7 Saum launched between 2850-2900 FPS have been positive. We've Never lost an animal or had any "failures", most animals are dead within sight or within 50-100 yards depending on shot scenario. The Closest shots have been right at 100 yards, the furthest being 775 yards.
I've found that they offer immediate expansion right on impact regardless of impact velocity.
The penetration isn't the greatest (Especially on elk. We RARELY get exit wounds) but they always punch through to vitals shedding a good amount of weight offering impressive wound channels..... (most of the time the wound channels are anywhere from half dollar size holes up to fist size wound channels depending on shot angle/impact velocity.)
I really cant say much bad things about them, they're boringly consistent terminally - I've yet to find a gun that cant shoot them at least 1/2 MOA or better.
The lot to lot variations in base to ogive can be a bit high, but most bullets I run have that same problem, even with the variations in BTO measurements they still shoot great.
Hopefully this helps your decision, we have stacked up ALOT of game with them over the past 3 years. Fully bellies and even better......FULL FREEZERS!