The food is hit or miss. Going with large groups is annoying -- you need to get your own food, and it's usually not ready-to-take - so they give you a pager the size of a 1980s cell phone and make it beep when your food is ready.
When I was there, I was injured and couldn't walk let alone carry my own food. My pager kept ringing as the rest of my party were off on their own adventure retrieving other dishes. The staff kept walking by and telling me to go get my food... I had to explain I couldn't... to 3 different Marche employees (what are these people being paid to do anyway?) My party finally returned from their adventure and they grabbed our steamed tomato-sauce-mussels, which were actually quite succulent. All I can say is... man are those pagers annoying!
Going with a large group is very blah as you feel like everyone is coming and going -- you're never really all there at the same time... on a positive note, it can be fun to try!