None of my previous iPhones had button problems, until the iPhone 4. It appears that Apples reduction in quality to enhance their profits is costing users. This is how the decline of BlackBerry began.
My 3GS was the best iPhone of any thus far. I'm encouraged that the 4S is slightly improved, yet I'm going to wait till the next model. Surely by then Apple will equip it with a modern sized display.
I believe the fear of less battery life is what's holding Apple back.