I take PPIs occasionally when my reflux raises its head. I don't have any problems when on the tablets, which I usually take for a month or so, and then come off them. In my experience, they definitely help and I don't get any side effects. However, I have found some more effective than others.
The other thing that does matter is when you take the tablet... It needs to be at least 30 minutes before a meal. Usually the doctor will say to take either in the morning or at night, but they rarely say that you should take it before you start thinking about the meal or cooking it! They work by reducing the amount of acid produced by the cells in your stomach. Once you are thinking about dinner, the acid is in full production so if you take your tablet too close to the meal or indeed after the meal, it cannot be as effective as the acid is already there.