It is the ammo that shoots the best from LCP. I sometimes carry it in my CW9 too. IMHO Hornady makes some of the best ammo on the market. The Critical Defense line of ammo was never designed to be the "legendary (read as imaginary) best ammo."
It was designed to fill a certain segment of the CCW market. The goal was to produce a low recoil for people that carry ultra lightweight CCW pistols. To reduce recoil you have to reduce power/speed. A bullet need to travel with enough speed/hit with enough force to to make the round expand. Lower velocity rounds have a history of poor expansion.
Most lower velocity rounds designed for similar purposes, like Speer Gold Dot for Short Barrels and CorBon DPX, use a very large cavity with soft walls to ensure expansion. Hornady used a different approach by tweaking their "flex-tip" bullet design. Basically, it has a little piece of rubber that is stuffed into it and sticks out a little at the tip. Rather than making the cavity get filled up to cause expansion (like a traditional HP). Instead, the flex-tip design as the little rubber bit get pushed back it forces the round to expand sooner. This is because the cavity is "pre-filled" with the soft rubber. The downside, is it takes less time to fully expand (causing greater resistance at an earlier point) and results in less penetration depth. Another benefit is that because it is essentially shaped like a FMJ round it feeds reliably in guns that are "picky" about ammo.
It is a clever design and by having the cavity "pre-filled" very reliable and uniform expansion is achieved. However, it does come at the cost of a reduction in penetration.
Like most things in this world, you have to accept the good with the bad and find an
acceptable middle ground. It is just a matter of what satisfies your personal requirements
the best.
So, is it "better" than Hydra-Shock or any other premium bullet design?
The answer is a "definite maybe," because it truly just depends on what you are looking for in ammo design.
-InkEd
P.S. One final thing it has going for it is by "pre-filling" the cavity it prevents it from becoming "clogged" and not expanding due to debris.