It's not even remotely the same experience as cattle-class coach. It's expensive, but if you have the money, it's worth every cent. Global Entry has let me bypass MULTI-HOUR-LONG lines for immigration. I hand over our passports and our Global Entry receipts, the agent scans them, and says "Welcome back." That's it. Security? Priority line, I don't take off my coat, belt, or shoes, I don't go through the naked scanner, and I only pull out my electronics because my charger bag has so many wires that it looks like someone's trying to hide a bomb somewhere (so I scan it separately, if they want to look inside, they can and it's a lot quicker).

It's not really fair. It really is me leveraging the fact that I have enough money to pay problems to go away. But it does work. And one of the reasons it does is that Precheck/GE people know the routine.