Buffers and springs do different things.
A strong spring and a light buffer will act differently as compared to a heavy buffer and stock strength spring.
Strong/light will achieve higher peak bolt carrier speeds near battery.
This is the place you want things to happen slowly to aid extraction and minimize bolt bounce.
My goto buffer combo is H2+ CAR spring, if I can't run an A5.
H3/blue is a fine combo, especially with an SBR.
IMO, it is silly to sacrifice reliability for a few ounces off the back end of the weapon.

