I’ve never been to Vietnam, but if you want the in your face, can’t miss destination, why not go to Thailand? I just got back from 3 weeks over there for the first time since NYE 2019/2020 and it’s still amazing. I’ve been to Cambodia too and while the scene doesn’t come close to rivaling Thailand and it’s significantly less safe, it was still pretty great. I’ve heard Vietnam can be a tough nut to crack, but Vietnamese women are definitely the hottest of the 3.