I currently have (in addition to - among others - the 70-200mm f2.8L II) the 24-105mm f4L and EF 85mm f1.8. The body is a 1Ds III. When I shoot (it ain't my day job), I shoot just about anything, from my children to landscape to sport to bands. My feeling with the 24-105mm is that the convenience is great, the max. aperture a tad small these days and the quality of image produced (ignoring aesthetics for the moment) quite good, but not stand out. Most of the reviews and comments I have read about the lens tend to confirm that - though it certainly has its fans. I am considering trading up to a 24-70mm f2.8L II and would be interested in hearing from those with experience of both lenses as to whether the improvement in quality has made the increase in cost worthwhile - or whether you hanker after the extra reach (or the IS) of the 24-105mm. On the 85mm front, again I know that the 1.2L II has cracking centre sharpness even wide open, but I have found the 1.8 a pretty amazing lens (in common with its FD/FL forebears), esp. for the money; I have found it particularly effective shooting gigs close-up to the band, giving an excellent balance of light and reach. I have read that the 1.2L can be slow to focus. But again I am interested in the experience of those who have tried both: if you do prefer the faster lens, what is it about it that makes the difference for you? Is it just about the extra light, or what? Of course, whether the extra money is worth it is pretty subjective. But it would still be interesting to hear why it was (or wasn't) worth it for you.