I was there mid to late afternoon and was seated immediately
Not required, they get very busy. I recommend calling ahead an hour or two.
My brother and I went on a Saturday evening and walked right in and we're seated right away. I can only speak of our experience. I hope that helps.
I would recommend a reservation on the weekends, it'll save you a wait.
It's not necessary at all, unless you want to sit in a specific area.
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