[Click] Is user-space Click more flexible and programmable than kernel-space Click???

[shule ney]

Hi all:
I have a question about the user and kernel space Click, no doubt kernel
Click performs much better cuz it resides in kernel and take place of the
original Linux network stack, so what's the meaning of user Click?? Is it
more flexible and programmable or is there some other advantage that user
Click have??? Thanks very much to reply.

Best Regards