First of all, a semi-disclosure: we were long standing customers at their Bay Ridge location and went into this dinner wanting to love it. No other connection.
We got there at 7:30pm (Friday eve) and only a couple of tables were taken. I was worried about the lack of business but, when we left at 9:30pm, the place was packed. It's now fully a/c'ed and the ceiling fans circulate the cool air well (previous poster's complaint). The servers are young and clearly being trained. Earnest & bright, but mistakes were made (minor). The owner (wife) was waitressing and going table to table to make sure all was well and giving them pointers away from the tables. The chef/owner (husband) was also in and out of the kitchen, stopping at tables to talk along the way.
The bread was okay (same as that served at Boullabaisse on Union: long, thin, dense, chewy, with flavor), served with sweet cream butter. The asparagus soup ordered by two of the four of us was excellent, but wasn't the "potato/leek soup, served warm" that had been described by the waitress as the "soup du jour" (that's the "minor" mistake I was referring to). Lucky both diners didn't mind the unannounced change. A dinner salad was fine. My seafood salad with whipped homemade mayo was excellent. Lots of seafood (peeled shrimp, mussels, crab meat...) over greens with a great mayo and light dressing. At $8.50 a very good deal. My boullabaisse was the same as what they served when in Bay Ridge: that is, a notch or two non-traditional. Anise and some curry in the broth. Very good, with abundant seafood and flavor. My wife's duck with berries (raspberries?) was also excellent. One friend had mussels and fries (cream sauce, not my favorite, but very good fries) and the other had a very nice salmon dish. We drank only one bottle of a good French rose and some ice tea.
For dessert, the owner picked out 3 pastries for us to share. An "opera cake", a vanilla eclair and a peach/pistachio tart. All were quite good. I'm not a dessert person but I think they were close to or on par with Marquet (which we love and who did our wedding cake over 20 years ago). Different style. He doesnt go for delicate (Marquet does, in my opinion); much heavier approach.
At any rate, we had a very nice meal and we'll be going back. Total cost was just under $100/couple (can be done for less if you dont eat as much as we do). For us, easily better than almost all of the other French places in the area (Jolie, Quercy, Bacchus, Pit Stop, Patois, Tabac). As a frame of reference, we like Boullabaisse as much. Since the owners live in the neighborhood and havent had a place for several years, we actually spoke to Jean-Jacques about other places in the neighborhood and found that he's friendly with Neil at Boullabaisse, goes to Pit Stop for food/petanque with his family, and loves Saul and Savoia. We told him to try Chestnut.