I'm not sure I'd sell the 70-200mm f/4L and 100-400mm f/4.5-5.6L in favor of the new 70-300mm f/4-5.6L. The image quality from the 70-200mm is amazing as it is, I don't think the 70-300mm could be anything but marginally better, and even then in real-world situations you probably wouldn't be able to tell. The constant aperture of the 70-200mm is a big plus, I didn't check but I'm betting the 70-300mm is only about f/5.0 at 200mm. Seeing that you have the 100-400mm, you might be disappointed with the reach on the 70-300mm.


What are your reasons for wanting to go full-frame? It seems like with your proposition you'd be loosing a lot of flexibility just for the 5DII. It also doesn't help that there are rebates on some of those lenses now, so you'll lose even more money on them.


What other lenses do you have right now? It's too bad the 17-55mm f/2.8 won't work on the 5DII, it'll make you want the 24-70mm f/2.8L.


Some food for thought on the Sigma 85mm f/1.4:http://www.youtube.com/watch?v=yIPFX2L9Ve8