I feel like the thing to do is to give whatever you are looking at in the showroom a pretty good shake, and to sit down on it hard. If it's creaky or loose at all there, it'll fall apart in no time at home
For now it is holding up and "feels" sturdy after a couple years, but I have no doubt it will fail at least 5 years before I would otherwise expect it to (I would want 10 years, but now expect 5). My fault for trusting Ikea + higher end = good without further verification.