I personally dont think resale is a factor, I never used a case or screen protector on my ipod touch, iPhone, iPhone 3g, or my current 3GS. I have sold all but the 3GS and received top dollar for them. I think if you take care of your possessions, electronics in this case, they generally don't get damaged or scratched. This is all my opinion, I feel the same way about the car bras to protect the front bumper of your car. Why cover up good design just to make it more valuable when you sell it.