I also did the Burger Hunt and ate so came across so many bad ones I just started leaving them on the plate.

Hands down the best burger in Zurich is the Park Hyatt in the lounge (basically the restaurant in the lobby). It is about 30chf which is alot but it is good...... really really good.

ZigZag is okay, but you cant go to the in the old town, you have to go to the one at Letzigrund = much better, aimed at locals, not nearly as good as Park Hyatt, but about 10chf cheaper and a more relxed atmosphere. I just heard this week that James Joyce has a good one but I havent tried it yet.

You should try both and let me know your thoughts.