I've been there several times. Last time I had a Cesar Salad and soup (I felt really, really horrible; I went back to the room afterward and was running a fever). That was mediocre at best (of course, I was sick). I've had their pizza before, different ones, and wasn't impressed. I can get better pizza two minutes from where I live for a whole lot cheaper (as in a big slice for $2 a piece).
It's not that it's bad, just extremely overrated IMO. It's actually funny because I'm a college student, so pizza is its own food group, and I don't really like Via Nappoli. I just find it overpriced and don't understand why people rave about it. Over $20 for a personal pizza? Don't think so. Much as I love pizza, I don't go to WDW to eat pizza. Especially not in Epcot.