He's only really just turned 27. He has 5 years at the very top, one last big contract and then 32 onwards he will probably start declining. 5 years out of a world class midfielder at £45M is fantastic business and exactly what we need.
Yeah 5 years out of him would make it good business, but there's no guarantee you get 5 good years out of him. Kante is 29 and his fitness and form isn't quite what it used to be. We bought Lacazette for 50m when he was 26, now he's 29 and he's showing signs of decline and no one will pay good money for him.
I mean if Arsenal actually have the money for it then I guess it's a gamble worth taking, but you've got to admit it's a gamble all the same.