fed ex is loud, but the loudest is arrowhead. lincoln financial is probably the hardest to play in as an away team id say
The Linc isn't even close. The way the stadium is set up, it's easy for sound to escape. And the capacity is not very large. I would say it's middle of the road and not nearly as good of a home field advantage as the Vet was. Now THAT was a tough place to play.
As for the Meadowloands, it's actually one of the quieter stadiums in the league yet can still be a difficult place to play. Why? They have very old season ticketholders who don't make that much noise- it's a very "old school" fanbase that doesn't readily give up their tickets to younger generations. My friends who have been to the Meadowlands for 'skins games all come away equally unimpressed by the noise, yet impressed with the classiness of their fanbase. The difficulty in playing there stems from the unique weather conditions that tend to effect the games- lots of swirling wind make the passing and kicking game difficult.