ok so i went ahead and sold my 70-200 f4L. Got a 70-200 2.8 IS instead. WHOEVER ever doubts the quality of this battle gun, should be judged mercilessly. This thing just rocks so hard! IS is forever. And NO its not softer than an f4. You just THINK its soft because you are crying tears of joy. It was well worth unloading semi trailers for 2 weeks