Let's face the facts. This is not a Canon 24-70mm f2.8 L and if you expect it to be, than you will be disappointed. If you want a very good 24-70mm f2.8, that preforms very well, this is it! It is not weather proof. It misses focus occasionally. f2.8 is not as sharp as f4 on.
Price
If you are expecting a Canon 24-70mm f2.8 L; forget it.