Flare on the 14-24, especially at 14mm can be very destructive on an image. If you are shooting into the sun, it's by far the worst as you will get a Magenta rainbow in the image towards the opposite end from the light source. It's not a great lens for sunrise or sundown when the sun it in the shot. I have attached two images to show this, note the strong magenta bands on the rock face. So far most times I can get this out using Content aware, but it's very dependent on where the flare shows up as to whether content aware can remove it.
You can see the effect in the both the full image and in the crop.
If you are shooting where the sun can reach into the frame, it will cause flare, but not as destructive as the examples. The 14mm focal length will reach around and fool you sometimes and produce flare, but more indirect. The best way I know to prevent this, is use the "flare Buster" setup. The large card with the longer extension so far has been able to block out in direct flare for me. It attaches to the flash bracket, but they also make one that will attach anywhere if you happen to be using a flash.
Also the Lee SW-150 setup, will many times block a in direct flare just due to the mass of the filter holder. Of course unless you plan to use the larger Lee or other brands 150mm size filters, it's too expensive just to block out flare. I use the SW-150 most times with the 14-24 and love it, leaving the mount on all the time.
One other aspect, night photography, I love to use 14mm as I can get a greater view of the sky and still have some good landscape subjects in the image. I stack, so if I have flare, I have to remove it from each image before I run the stack. Flare at night can be even more destructive and for sure more time consuming to correct. At night it's the moon causing the flare, I prefer to use moonlight to provide illumination to my foreground and it give the sky a much more pleasing color. The moon creates a more pure magenta/yellow flare and the flare will change in shape as the moon moves across the sky during your shoot. Again I have found the flare buster card to be invaluable to prevent this.
The 14-24 is however such an excellent lens, at least mine is, that I am more than willing to find workarounds for this. Just be aware that it's going to bite you if you are near a strong light source.
Paul Caldwell