If registed with the PE, having your entity hover above the ground is very likely to lead to undesired results since you would have to apply a constant upwards force to counter gravity....very unstable.

And if this is a workaround to the stairs, consider that to climb stairs, I would simply disconnect the engine, start my stair climbing animation, and ent_move the player diagonally up the stairs. Once on top, I reconnect the engine and proceed as normal. I can't forsee any circumstance where it would be advantagous to have a PE registered entity float above the ground.