-Phytic acid content (hinders digestion and nutrient absorption)
-High omega-6 content (conducive to an inflammatory environment)
If you love oats, or if they work well for you, by all means keep eating them. For digestibility and nutrient profile purposes, I tend to prefer and recommend grits.
Fiber one bars are "OK." I think that for convenience sake they are acceptable, or for a snack. You would benefit more from eating oats, grits or something like cream of wheat/rice.