Is using underscore suffix for members beneficial?

class C {
 private:
  int member_; // here is the underscore I refer to.
}

This underscore is recommended by Google Style Guide and Geosoft's C++ Style Guide.

I understand that there are different opinions and tastes.

I want to ask people who used it or were forced to use it whether they found it beneficial, neutral or harmful for them. And why?

Here is my answer:

I understand ask motivation behind it, but it does not convince me. I tried it and all I got was a little bit of clutter all over the class, but simpler initialization of members in constructor. I haven't encountered situation where underscore helped to differ between private member variable and other variable (except in mentioned initialization).

In that light I consider this style harmful.