I am needing an "in between" lens. I currently have the 17-55 f/2.8, 70-200 f/2.8 IS, and 50 f/1.4. I often find that the focal length of the 17-55 (while an awesome lens) isn't enough, and obviously, the 70-200 is way too much. I have an event coming up that I will be shooting - indoor, low light - and I need another lens to fill the gap. I'm afraid the 24-105 is a bit out of my price range at the moment, as much as I would love to get that one. What about the 28-135? How is that lens? And what about the 18-200? Is that lens any good at all, or not even worth batting my eyes at? Any advice or recommendations that you could give would be greatly appreciated. I'm looking for any sort of insight or opinions. Thanks in advance!

