A couple I haven’t been, but the only one I’ll differ from onzieme is Les Enfant du Marché.
I find the food very good usually, and occasionally great. My comments on my visit last year here. The mussels with Gorgonzola alone are almost worth the visit for me.
I plan to return for lunch next month, but as SteveR notes, we’re in Paris for several weeks this year. As long as you know you’re going to something that’s more covered outdoors counter than sit down restaurant, I’d encourage you to go if you’re interested. Though I agree it’s not a must go.