Ah, funny thread. Here are my impressions from germany:
McDonald's: okay, but too thin and salty
Burgerking: allright but nothing to hype
Local "Pommesbude" (Pommes = french fries, Bude = tiny store): Awesome, if you're able find the best Pommesbude in your area.
We have a lot of tiny Fast-Food restaurants here in germany. Usually, they sell Pommes Frittes (french fries) and sausage with Curry-Dip. One can say, if these two products are tasty you've found a good Pommesbude.

Btw, we want mayonnaise on top of our french fries.