TriX wrote:
👍👍 the 16-35 f4L IS is one excellent lens (and tack sharp), and as CHG_Canon said, (unless you’re into astrophotography), how often do you need anything faster than f4 for the type of shots you usually use a wide angle for, and how often do you need anything wider - I never have. If I didn’t already have a 17-40L, I’d be purchasing one.
The IS is what moved me off the older 17-40L, another great lens and a bargain in the L lineup. Doing a mental inventory, probably a third of my lenses are IS-enable. You don't need IS / VR / VC that much in a wide angle, but I can use it in low light in situations well beyond my ability to hand hold. I can also hold the camera in unsteady angles and use the IS to capture some interesting angles. As a rather old design, look for used 17-40L copies rather than full-priced new.