Rating: 20/10 The late Chadwick Boseman, star of Black Panther, arrived with “a really big crew,” according to Mercedes. And he gets the highest rating in her series for being the “most respectful, nicest celebrity [she’s] ever met.” For more celebrity news sent right to your inbox, sign up for our daily newsletter. Rating: 20/20 Mercedes served actor and comedian Adam Sandler, along with his wife and children, and said he’s a “personable” guy. “He was nice as can be; he didn’t say one rude thing to me or give me attitude,” the server continued. “He was really funny and just full of laughs.” And for what the critics think of Sandler, check out Ranking Every Adam Sandler Movie, From Worst Reviewed to Best. Rating: 9/10 Mad Men star Jon Hamm also gets high marks, though Mercedes was surprised that, instead of having an entourage, “he was always alone at the bar…playing games on his phone.” The unlikely loner “was just really sweet,” and “overly nice to you all the time.” To find out how celebs behave while they travel, check out A Flight Attendant Is Ranking Celebrities Based on How Rude They Are. Rating: 7/10 Mercedes called host Conan O’Brien “a really nice guy,” but withheld a few points because of his unusual breakfast order. The server claimed that the comedian prefers to start the day off with rice, which was “annoying” because they didn’t have it to serve. And for a celebrity O’Brien doesn’t have good memories of, check out The Worst “Late Night” Guest Conan O’Brien Ever Had. Rating: 7/10ae0fcc31ae342fd3a1346ebb1f342fcb The tech mogul was supposedly eating lunch with a woman who had to leave the table and give him privacy any time he took a phone call. Mercedes’ other complaint is that he didn’t go big on the gratuity. “You would think he would leave a really big tip,” she said, “but he tips just exactly to the dot, which is probably why he’s still really rich.” For the perspective of someone who dresses celebs, check out A Celebrity Stylist Is Rating Stars Based on How Rude They Are. Rating: 7/10 Even though she serves “the 1%,” Mercedes said the whole room was still “shocked” and starstruck when Oprah Winfrey arrived. While “she wasn’t really mean,” the server explained, Winfrey didn’t get a perfect score because Mercedes “honestly talked more to her bodyguard than to her.” And for the one person Winfrey probably wouldn’t want to talk to again, check out Oprah Says This Was the Worst Guest She Ever Had. Rating: 5/10 Emily in Paris actor Lily Collins was “really polite,” Mercedes recalled. But she was also “standoffish most of the time,” which made it “awkward to serve her.” Rating: 4/10 Zendaya, known for her HBO series Euphoria and the Spider-Man movies, was put off when she was told that her hotel room wasn’t ready for her yet, Mercedes said. “So she was really mad and was not happy to talk to anybody,” the server continued, claiming that the star “directed [her frustration] towards everyone.” For one star’s less-than-stellar experience with a celeb, here’s James Corden Says This Is the Rudest Celebrity He’s Ever Met.