Merchant Boeuf is a fun place with good cocktails and a mix of good live music or dj's. I always have a fun time here, unfortunately the food is really inconsistent. Have eaten there three times - first time good, second time bad, third time average. It is also slightly overpriced, but so are many places in the neighborhood.
I am torn on this place though because I really do like the atmosphere, music, staff and cocktails. Go for a good 5 a 7, stay for some music, and if you need something to nibble on go for a noncommittal appetizer and save dinner for later.
One recommendation would be the tartare sampler which I actually liked. Stay away from the raw bar.... not a disaster, just not at all tasty.