"I'm happy for him," Clooney's Gravity director, Alfonso Cuarón, told PEOPLE at Tuesday's Time 100 Gala in New York. "To me George is a terrific and a fantastic person. As a husband I think he will be the same. He's a guy who is so generous and respectful, and I think he will be good at marriage, too. George is also genuinely honest. And, it's so much fun to be around him."
Clooney's close friend Charlie Rose, co-anchor of CBS This Morning, says the Oscar winner shares the same interests with Alamuddin, 36. Rose also has gotten to know Alamuddin, who attended a conference that he hosted in Aspen last year.
"George has a very serious side to him," the veteran journalist, 72, who has spent time with Clooney, 52, at his home in Lake Como, told PEOPLE. "He's a prankster and a damn good actor, but he also cares about issues as she does."
"Amal is incredibly accomplished and has a substantive legal mind. I have a lot of admiration for what she does," Farrow, 26, told PEOPLE. "She's tremendously charming and beguiling. Just look at her career. When I'm ready to do an interview on privacy law or when I'm interviewing someone connected to Julian Assange or Glenn Greenwald, she's one of the people that I turn to. She's wonderful."
For Martha Stewart, who is a fan of Clooney's films, she was happy to hear that the Hollywood heartthrob finally decided to settle down.
"I thought it was about time!" Stewart, 72, told PEOPLE. "They make a great couple."
Stewart has got a recipe recommendation for the bride-to-be, too – if she ever finds time to cook.
"George is a healthy eater. She should make one of our one-pot meals," Stewart said. "It's a new book that is coming out and everything is made in one pot like pasta and chicken ... They have busy schedules, and making a one-pot meal, they can prepare healthy meals in a quick and easy way. I think that's a meal he will enjoy."
For much more on George and Amal's engagement news, including an exclusive photo of the ring and a closer look at the woman who won the heart of the ultimate Hollywood bachelor, pick up this week's issue of PEOPLE