The diminutive Ruger LCP is lighter, shorter and thinner than my assortment of J-frames, which includes steel, aluminum & Scandium (aluminum) framed models.
As a longtime DA/DAO revolver shooter of J's, I found the LCP to be easier to shoot than I expected. Despite its rudimentary sights (even worse then the old narrow/thin J-frame irons), it was surprisingly accurate. It also fed & fired well with some different hollowpoint and ball loads I tried.
The takedown pin walked a few times on mine under recoil during the first 100+ rounds, but a replacement pin from Ruger resolved that minor complaint.
The ability to carry the LCP in a pocket (holstered) that's too short to accept one of my J's was the primary reason I bought it ... after not having wanted to own a .380 in the more than 25 years since I briefly owned a Beretta M84.
As has been mentioned, the LCP has proven too small for a couple of other instructors to be able to shoot it because their hands were too large to allow them to easily manipulate the little gun, but it's more than adequate for my medium-size hands.
I've seen one other fellow experience some issues when shooting his LCP using 2-hands. He experienced repeated stoppages because he let one of his thumbs repeatedly rub the slide during cycling (one of those high/neutral thumb shooters). When I pointed it out to him, he moved his thumbs and the little LCP perked right along with aplomb. It reminded me of how Walther PPK/PPKS shooters could induce stoppages when they let the web of their hands run up against the bottom/rear of the slide, or thumbed slides.
I haven't looked at the newest LCP with improved sights and trigger, but my 2012 production model seems fine for my needs ... which is when one of my J's won't easily or properly fit in a jeans pocket.
Handy.
If possible, though, try to arrange to try one out on a range before buying, as itty bitty pistols (and 5-shot snubs) are often difficult for some folks to shoot well.
I suspect this is why the larger .380's continue to sell to some folks. I imagine the larger Ruger LC380, and the new Glock G42, will sell to folks who need something a bit larger than the LCP or Bodyguard .380's.