I agree in principle with the 24mm TS-E. However, given the fact that my vacations are not just photo-safaris, but taking two impatient teenagers to see the world, I would choose otherwise for the time being. I just went to NYC last week to shoot "urban landscape", and it rained all week (making changing lenses impossible with an umbrella in one hand and millions of people bumping you on the street), and the aforementioned teenagers (who already walk faster than I do when I'm just walking) unwilling to stop while I composed a masterpiece. I took a big kit carry-on, including 6D, 8-15mm, 50mm 1.4 Art, 16-35mm 2.8 ii, 24-105mm Art, and 70-200 2.8 ii plus teleconvertors. But, the only lens I used all week (except for my iPhone6 + for panoramas and when it was just plain raining too hard to take a camera at all) was the Sigma 24-105mm Art. Would I have liked to take some longer shots? Sure (but in the fog and rain couldn't go too far down range). And, would I have liked to go 8mm on top of the Empire State Building? Sure. But, it just didn't happen. Sooo, practically, when the kids are gone, one lens only, the 24 TS-E. But, given what I just went through (endured?), I got a lot of memories with another choice.
p.s. I used to use the big white EF 35-350mm which was great, but sold it since DxO didn't have a module for it. Still a great single lens choice to get a little bit of everything. That plus the 24 TS-E for perfection.
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