i have always free fed and overeating is never a problem. I see mine eating several times a day but they eat only a few kibbles at a time. They know their food will always be there so they don't worry.
feeding on a schedule is too hard if you want to do something or go somewhere. You should be feeding kibble anyway because of their teeth. Potty training is not a problem either. My adults are trained to use a pee pad and the babies soon pick it up. This is a great help when the weather is bad and they can't go outside.