I would hate to be at Mason's for mother's day, personally. It's going to be an out of control cluster frick and the food really isnt that great.
Never been impressed with the place either.
Last year, I did the special occasion Sunday brunch at Fleming's for Mother's Day. Everything was on point and delicious. I made reservations far in advance, so I never had to wait for anything, and I never felt rushed out.
That said, I try to avoid restaurants on those holidays.