You can benefit from using MFC and C run-time portability features even if you do not currently intend to internationalize your application:
Coding portably makes your code base flexible. You can later move it easily to Unicode or MBCS.
Using Unicode makes your applications for Windows 2000 more efficient. Because Windows 2000 uses Unicode, non-Unicode strings passed to and from the operating system must be translated, which incurs overhead.
Using MBCS enables you to support international markets on Win32 platforms other than Windows 2000, such as Windows 95 or Windows 98.