I've only gone to the Grand Concourse a few times and each was a special occasion / weekend to celebrate (Mother's Day, Birthday and welcome home events). We not usually the plan ahead / need to make a reservation couple; but this place is worth it.
The atmosphere is awesome, it's so nostallgic; but pricey. This is not a get in and get out kind of event / place. So, sit back and enjoy.
Don't miss the donut machine in the bar area. Of course there are buffet table with different brunch selections, but usually there's an omelet station, carving station, bananna foster guy... oh the dessert table, along with juices in punch bowls.