I am a soon-to-be owner of a 5D3, and right now I am looking at my lens collection and planning what I need to upgrade. One of my main interests is low-light photography, and with the 5D3 I will be able to move into the "extreme low light" area, and for that purpose my lens collection is just about perfect anyhow.
However, a secondary interest is landscape photography. On my crop camera, I have the 10-22 EF-S lens - maybe not spectacular, but good enough - however, once I get my 5D3, I need to replace that, as I will then have nothing wider than 24mm (well, apart from a couple of fisheye lenses, but...)
So, the 14mm f/2.8 might be the "obvious" choice, but I am wondering about the 17mm TS-E as well. It is wide enough for my needs, and the til-shift might be interesting to play with. There are other possibilities of course. The Samyang 14mm looks like really good value, and if price was an issue, I would probably consider it. The recently announced Zeiss 15mm is incredibly sharp wide open, but to me it looks like a solution to a problem I don't have ... for my purposes, sharpness at f/2.8 is irrelevant - what I want is top sharpness at f/8-f/11, and there I don't see the Zeiss outperform the 17mm TE-E, for example.
Now, other concerns: distortion is not a serious issue for me (landscapes, not architecture - so no straight lines anyhow), but low CA and edge sharpness would matter a lot more to me.
I have been reading various reviews and comparisons, but I just cannot make up my mind, so I am asking for advice from those with actual experience in using those lenses for this purpose.
So, which lens would you recommend for my needs?