Yeah, I've done searches on this and many other sites and find that most who actually use this lens love it, those who put it down generally haven't used it, say you might as well buy a P&S, that 5.6 is too small or that is is too expensive. While I agree with these statements I also know that when travelling (especially in south China) the conditions are always changing and there are so many shots near and far, add to that the weather seal. I'm a big guy and am used to lugging around my gear, hell, I carry it just about everywhere I go. If I could bring the 28-300, my 17-40 and perhaps my 35, seems for most situations I'd be able to leave the 28-300 on the mkIII. Can always fill flash with the 580II
Hell, there'd be room left in my bag for a bottle of water and some snacks