Morning all,

Firstly let me apologise if this has been covered before, I've had a search but couldnt find anything.

I'm tossing up between these two at the moment.

Trying very much not to be sucked in by the "L" and rather going for something that will both give me great results and and provide me with what I need.

At the moment I have a 50D and the 50mm f/1.8. I've enjoyed playing with the 50mm so far but am finding it limiting when wanting to do landscapes / architecture, which is what I want to get into next. I do have a 70-300 sitting on my desk which is borrowed from a friend so I do have zoom abilities when needed, although not with a very good lens.

The 17-40 would fit nicely in front of the 50mm and give me the wide end I need. Obviously it performs as an L lens should also. Doesnt have IS though.

The 15-85 gives me a bit more in terms of width and obviously quite a bit extra reach than the 17-40, overlapping the 50mm and going that extra bit past it. It does however not have a constant appeture. Reviews on this are good so far. Does have IS.

Be aware that my plan is to get a whole kit as time goes on, so while my kit is lacking any kind of real zoom at the moment (If needed I use my 18x FZ35) it is my intention to get something in the future, I havent wished for it yet though. My next will probabaly be an UWA assuming I enjoy the landscapes.

What are peoples thoughts?