I was in your particular situation, personally, and know how much SVN has improved the situation there. In my current situation we had a problem just yesterday that SVN would have prevented. But, as several others have pointed out, since there were only two of us who were supposed to be working on the project, we thought that coordination would be sufficient to prevent problems. We have been proven wrong!

This morning we found a line of Perl was missing from a file. No idea how, who or when, but it's gone. Luckily, we do have good backups, but we are testing revisions, and it has held us up for several hours before we found the problem.

Guess what, I will be setting up SVN at my new site, and urge everyone to take similar precautions!