I used it for my sister's wedding reception - 18 of us in total. Saved some serious coin off the default prices. We brought our own wine too. They charged a corkage fee but it was still alot cheaper than buying their wine.
Here's the thing- like most casino restaurants the default prices are elevated compared to non-casino restaurants of the same echelon. Just look at the menu prices - $20 for a bowl of soup.
Thats how they dilute player comps. So 25% off really just brings the price down to what you would normally pay for that meal in an off-premise restaurant.
But still, you get the nice view and famous location....so it makes for memorable evening. enjoy