noctua nf-a15 hs-pwm 140mm

Hey guys, is it worth upgrading all of my stock fans? Currently, I'm using the stock fans of my case ( Phanteks P600S, 2 140mm in the front as intake, 1 140mm in the rear as exhaust, nothing at the top) and I'm thinking of removing all of them and putting 3 Noctua NF-A15 HS-PWM 140mm in the...