If you're cooking at neapolitan temps, cooking on steel will burn your crust very quickly. The reason for the steel in home ovens is to get high heat transfer (high conductivity of steel) at lower temps to mimic how brick/stone works at ~800F -- mainly for oven spring (I believe).
I don't have a G3, I use the Newwave stone bake pizza oven from walmart. I've measured stone temps at 850F. Picture below is from my unmodded oven.