I have GERD, and I've been on PPIs for 4+ years now. The meds work very well, but the GERD symptoms wax and wane constantly. Sometimes, the aciphex I take takes care of the symptoms completely (actually most times it does), but I routinely have breakthrough acid. Therefore, I supplement the aciphex with zantac every night before lying down, and with rolaids/tums throughout the day on an as needed basis.
You can always experiment a bit by stopping the PPI for a while and seeing if the symptoms dramatically increase, and then start taking it again to see if the symptoms go away.
El