I like my 16-35 II, it's just not that sharp wide open, especially if the subject isn't close to the camera. But at f/4-f/8 I've gotten some very sharp pics with it. But as soon as I got the 14L it made the 16-35 seem soft.
I want to get rid of the 16-35mm and get the Zeiss 21mm f/2.8, but I shoot a lot of bands in very small places and some of them have 2 members and some have 6, so it's nice having the 16-35 to quickly adjust the static cam. I'm just worried that if I get the 21mm there may be cases where it's not quite wide enough and the 14mm may be too wide. Damnit why does that thing have to be so useful!