A lot of people gripe about VSS, and afaik it isn't even used internally at Microsoft (at least not for the larger parts like the kernel - they have something else for that). I've heard more than one tale about database corruption etc.
In my experience, subversion adds very little overhead in single-developer projects - the initial repository-creation doesn't take long, and after that it's basically just committing your files (in one go) and writing a changelog when you've made enough changes; this is something you should be doing anyway
Oh, and you don't need to set up a subversion server, it can operate directly with file:// URLs; I'd still set up svnserve even for single-developer use on a single machine, though, and set up DNS entries - that makes it easier to move the repository to a server later on.