You don't like 'gimmick' bullets but you like the Lehighs. It's called a gimmick bullet, too.
Your friend's gun doesn't function well with the ARX ammo. Then it's not for his/gun. But that's just one gun, and you can't judge it based on just one gun. You have to try any new ammo in your gun to see if it operates reliably. No exceptions. I've fired the ARX in 9mm, 40, and 45. No function problems. They do have less recoil than most ammo, and this might be a problem for some guns. Reviewers have had good reliability with this ammo.
Plastic bullets are a stupid idea according to who? You? Thanks, but most of us will trust the advice of qualified experts over you.
No, the ARX does not look just like the Lehigh bullets. A dark brown round nose ARX does not look like a copper flat nose bullet. Maybe to you, but not other people.
Speed is a "gimmick" but not if Corbon loads it? Right.
"gimmick" Bullet reviews from professionals:
https://www.americanrifleman.org/articles/2015/10/23/tested-the-polycase-arx-bullet/
https://gunsmagazine.com/discover/fluted-ammo-great-or-gimmik/#:~:text=On average, the Advanced Rotation,yet produce much less recoil.