I have the T3i and the 17-55 2.8, it takes a special circumstance for me to take it off and put anything else on. I use it for the vids, stills, landscapes, etc. I went through the 15-85 upgrade (want it? it is for sale) and found that pretty much anytime indoors it was too slow - if I am going to be outside and can only take one, it MIGHT remember to take the 15-85. I also have the 70-200 II, and have a small bag that I take that fits it, the 585 and a couple gadgets, straps a mono/tripod to the bottom and this covers just about any day trip I might take.

24 is not nearly wide enough for a crop body and if you think about it the 15-85 covers the same effective range on a crop body vs. full frame as the 24-105. The 17-40 stops short in both reach and speed. You will quickly forget the few extra dollars spent, unless you don't spend them and can't get the shot cause you have a slower, shorter lens... Then by gosh you will remember the decision and most likely apply say or think something not best expressed out loud.

Quote Originally Posted by DJ 86 View Post
even i had same question in my mind.
as a replacement for kit lens, if i am using 17-40F4($885) or 24-105F4($1000) which is a better choice?
i think many will suggest for 17-40 for its 17mm wide end. but then i can also consider tamron 17-50 non VC which is quiet cheaper at F2.8 and also delivers sharp images.
what opinion do you guys have??