I plan to fry up a big batch of fries tonight as a special request for my weekly football party. I'd rather not have to miss the game to cook them in multiple batches as people come and go. I know fries are best fresh, but in attempt to have them edible for a bit longer, what would be best to keep them warm? I planned to do put them in a low oven at 200F. Would that work? How long would they stay "fresh?"