If you want to know which query are slow and need to be improved yes it's better to use the sql profiler. But this is not my goal.
I want to have, for one webmethod call, the time taken by different parts when the request reach the server: unzip, unserialization, business time & sql time, serialization, and finally zip. (soap message can be bzipped). The network time will also be available because I'll add some code on the client side.
With the sql profiler log, you cannot link the sql query to the webmethod that made it...