I eat oatmeal (old fashioned) practically everyday. I prefer to eat them in the AM, because they have slow releasing carbs, and brings sustained energy levels, and with me a feeling of fullness that lasts most of the day. Practically every day, I say. However, the draw back I get is I tend to hold more water when I consume it temporarily, but on big lift days (chest, squats, back), I make sure I have this in my diet. More water, because my front ab skin seems thicker than when I dont, and I have experiented for myself to find out whether its this or not.
I like the feeling it gives me, and just taylor the oat consumption in the AM so I have it for the entire day or most of the day---along with other differing sort of carbs, if you get what I am saying. Oats are fantastic.