No benefits over high pressure. Ions are reccomended to have a high pressure tank because there were tanks being made with a slow recharge rate that couldnt keep up with the gun. As long as the tank has a high recharge rate it will be able to keep up with the gun.
Edit: beat me on that one spug
DSDM:Well at least you are alive to tell us about it. You didn't luck out and die and get out of your marriage easily.