The 23-year-old has scored nine tries in six matches in the current campaign so far, including a second consecutive hat-trick on Saturday, but will depart later this year after signing a two-year deal with the Premiership outfit.
"That's the landscape of rugby at the moment; boys are feeling like they need to go overseas and take opportunities, but he's going to be missed, that's for sure," Kirifi said.
"Everyone sees the on-field stuff obviously – scoring tries, his attacking prowess. But he's a smart, smart footballer. He learns fast and applies things really well throughout the week.
"It's no surprise he makes these plays, because he's done the work. He's an awesome young man."
Fineanganofo was central to the Hurricanes' 52-14 win over the Queensland Reds as Clark Laidlaw's team retained top spot ahead of a two-week break for his side, who sit at the summit despite playing one game fewer than the Auckland Blues.
"It's his career and he's made a decision that he thinks is right for him and his family," Laidlaw said of Fineanganofo.
"Who knows, he might be back? The world is a transient place now. You can go and come back. He's only 23. If he stays and he's not an All Black then maybe everyone says he could have taken the opportunity overseas.
"We're just loving the way he's playing. I've seen that for five or six years now how quickly he can change and adapt his game and grow.
"I don't care about next year. He's here this year and we'll make the most of it."