My surgeons say 10 years on average. There are some who go twice that long and some a bit less. Some people do have to go back on PPIs. I would not say it's a failure though. They can't make you completely reflux free or it would be near impossible to get anything into your stomach.
Pretty much all people have reflux to some degree, but not everyone notices it.
Nissen 6/06 and 5/09
#3 on 8/24/11