We enjoy the Festival -- and we think the food at the booths has only gotten better over the years. Plus, they have increased the drink selection to include not just wine but some fun things like Singapore Slings and frozen Mohitos. There is also lots of beer (too much beer really these days), but for those that like beer there is . . . well . . . lots of it.
Unlike an above poster, dh thinks Epcot would be boring if the Festival weren't going on, so that is the only time we visit.
Do be aware that, as the pp said, one can spend a good deal sampling at the booths as the prices are, basically, $3-$7 for food and about $4-8 for drinks. We easily run through $70 or so on one walk around world showcase tasting things that appeal. But, it's fun, we enjoy it as a substitute for lunch, and we would likely spend $50 on lunch anyway.
Also, weekends can be insanely crowded. We stopped by on a Saturday last year and the lines were 30 people long. We just left and went elsewhere for lunch. Also, due to all the beer available, Friday and Saturday nights tend to feature packs of young men barely of drinking age staggering through the park. Dh saw a CM and a drunken young man nearly come to blows last year. We now avoid weekends.