Slides out or autolevelers down first?

Checked with Newmar concerning this topic and here is why always have air up,means slides out first, especially with the long side. First air will not be up if unit is leveled first. Coach frame has less chance of twisting if on the air bags, not the jacks, this means more support for the entire coach. My long slide will move with the engine running, but the shorter slides will only move with engine off.
Ole B