-@warning <b>S4U is not ready for public use yet</b>. You should not go
- that path unless you know what you are doing. If unsure,
- proceed to @ref MSG_API instead.
+@warning <b>S4U is still evolving: v3.18 is a beta release</b>. You
+ are really welcome to test it, but this API may change
+ between releases. This is however the way to go if you want
+ to create a new long-term project. If you want to play safe,
+ proceed to deprecated @ref MSG_API instead.