Canon 17-40 l lens

I had the 17-40 and it was a good solid lens. No issues, and I think it's generally a proven lens. A great travel lens as you won't have much invested in it. I sold mine after I upgraded to the 16-53 f4 IS.

There might be better lenses out there.

But at the used prices they are going for you cannot really go wrong either.

With all the available information at least you know exactly what you're gonna get.

Very safe choice.