Sel spd
A few reasons I've used selected speed is if Vapp is right on Vls. Otherwise G/S mini and ATC asking for minimum approach speed.
Not sure how much micro managing your company does (someone says you'll be in the office for selecting speed? Crazy).
Anyhow managed speed is a great tool and awesome 99% of the time. But don't over think it if you want to do something different. You could always change Vapp in the box if heavier than GW, but on short final ask the PM to select a speed (or just fly a couple kts fast if a/thr is off).