Are all CL shoes uncomfortable or just certain pairs? I tried on a pair while waiting to purchase Monolos and the CL didn't have any padding and were not comfortable.
It's not all pairs, it's whatever doesn't work for your feet that is uncomfortable. Many, but not all, find Simples comfortable and Pigalles, Decolletes, Clichys painful; at least at first. Sometimes it's the other way around. Again most seem to swear by Very Prive as very comfortable. You can always put padding in, but once the shoes are broken in, they will most likely be comfortable anyway. There's only one way to find out what works for you