Hi Jerry:
Guess that was you I saw at the Quidi Vidi on Sunday morning. You are the first other person I have seen with this lens. I love mine and it is my most used birding and other wildlife lens. The more you use the 70-400 the more you will like it. It is capable of incredibly sharp pictures as you get used to it. With our light, or often lack of it, a tripod is often helpful. Keep at it.
Gene