I currently have 700x23 on my road bike. They are Continentals and I like them but I feel like they will be sort of light weights when I begin to tour. I am sure that I will be hitting some dirt roads (light to no panniers) and I was just wondering if I would be better off on 28s. I am a woman of weight! I also don't want a bunch of flats. I just want good reliable tires that are comfortable. Ideas?