I currently have a Tamron Autofocus 28-200mm f/3.8-5.6 XR Aspherical as my walk around lens for my Canon Rebel XSi. I really enjoy using it, but I am starting to get frustrated when trying to use manual mode and I can't stop down enough to get good shots without flash. The lens also sometimes causes the camera to decide to focus on the wrong aspect of a picture (this could be a camera body issue, but I rarely have the issue with my other lens). I would like to upgrade my walk-around lens and am looking for suggestions. I do not need professional level lens, but I would like something that has better glass, wider range of f/stops but still has a decent telephoto range at the top. I also have a Canon f/1.4 50mm for portraits, but because my camera isn't a full frame body, it won't get wide enough for everyday use. Any input, suggestions or other info would be greatly appreciated. Thanks!