namespaces and static class members

Say I had

Code:

---

using namespace algo {
  int func() { return 5; }
};

---

and

Code:

---

class algo {
public:
  static int func() { return 5; }
};

---

Is there any difference? The only one I can find is that you can declare all the members of a class friends where you can't with namespaces.

If the only purpose for your class is going to be to contain these static functions, then I see reason to prefer one over the over (aside from preference, that is). The one downfall classes have (if they are being used as namespaces like this), is that you have to declare away the constructors to prevent one from ever being created.