These days I use Argon exclusively for my bottles of top up wine for my barrels. Depending on how much I have left over on each varietal it could be a gallon or a Magnum or just a 750. Each week I top up the barrels and then flush the headspace in the top up bottles with Argon and stuff the tasting cork back in the bottle or screw cap. Rinse, repeat every week. Keeps the wine from oxidizing as the headspace grows but one week is MAX without a top up of gas, even with a cork or cap stuffed into it.
