The iPhone 6s Plus is much stronger than the previous version. The question remained, how much stronger. As you'll see in this bend test video the new model survives 100lbs of force without any permanent damage. Case separation occurs around 150lbs of force. This new 7000 series aluminum appears to be a huge improvement over the previous 6000 series. I can confidently say that the iPhone 6s and iPhone 6s Plus are significantly stronger than the previous models!