Which wide angle do I but,

I have a 5D Mk II, my standard lens is a 24-105L.
I am going to buy a wide angle zoom but cannot decide on either the 17-40 L or the 16-35.
Is the 16-35 worth the extra money (nearly double the price) for one stop wider in aperture and 1mm extra in focal length.

When I had my 50D, I used a 10-22 and the 10mm wide angle was great for landscapes. The 17mm on a full frame is almost equivalent .

Any suggestion from people who have either of these two lenses.

Almost in the exact position as you. Shooting a 24-105 atm on my 5D Mark II, used to shoot a 10-20 on my 550D. For landscapes, just go for the 17-40. The price is just too big a difference. If you use it and often want an image that's just a tad wider, or often find that it's a stop or so too slow, switch to the 16-35. But it's not an urge I'd expect to have.

For journalistic purposes the 16-35 is a dream lens. Fast for relatively shallow DOF and great AF even at ultra wide focal lengths. But since I make do with f/4 on my 24-105, I figure I can make do with f/4 on the 17-40.

if you don't need f2.8, get the 17-40. i tested them both side by side here over Christmas when they were on sale, kept the 17-40. there wasn't much difference between them.

For landscapes.. save your money and grab the 17-40L.. both offer similar performance when stopped down, which is what you do in most landscape shots. I'm sure you didn't shoot landscapes with your 10-22 @ 10mm f/3.5. :P

I shoot landscapes smaller than 2.8.... Just sayin'

Only you can answer this question - do you need 2.8 or not? If you don't know, then you may not.

There are other differences between these lenses, so don't automatically think these are identical except between 1-stop and 1mm of length. There's much more differences that can certainly be worth the $ price difference if you need it.

Thanks guys for your suggestions.
Cheers from DOWNUNDER.
Bob.