I use git at work because we were told to, but I am actually quite fond of it. I've even started using it to keep track of personal projects at home.
I like it because it has pretty good documentation and I can figure out most of what I need with a quick search, and because it generally does what I want when I want it to.
We switched to git from cvs about a year ago, and I am much happier for a few reasons that will also apply to subversion:
1) Repository info is only stored in one place, so you don't ever need to search out all of your CVS or .svn directories
2) Local commits make it easy to check stuff in whenever you need to, and then make it pretty (with git rebase -i commitid) before pushing to a central repo (assuming that's the model you are using)
3) There is a two-stage commit. You have the working tree (aka working copy), which is what you are editing, the 'index', which is where the changes you want in the current commit go, and the actual repository, which holds commits. With that extra step in between, you can check in only the parts of a file that are relevant to the current commit (with git add --patch filename). I have a tendency to do a bunch of editing everywhere, forgetting to commit, and then go back to make multiple commits of discrete features/bugfixes at the end of the day. I'm pretty sure you can't do that with CVS, and although I'm not sure about subversion, it would surprise me if you could do it there.
4) The repository keeps track of changes across multiple files, instead of tracking each file individually. That makes applying a bugfix from another branch really easy, since you don't need to hunt down every file that was modified by it.
So anyway, I'd suggest sticking with git, but there's no harm in trying other systems; you never know, what I like and what you like may be completely different.