We use it at the office. We're about 10 developers, and 20-25 people reading and checking out various non-java files as well. It's pretty stable and it has nice features. Being able to force locking on some files is also a plus.
Subclipse lacks one feature: when you ask for a list of files to commit, you can't pick one of the files in this list and ask for a diff (as in: what the heck did I do in *that* file?). The tortoise shell integration can do this.
It's not particularly fast. Especially if you have 5 projects with 5000+ java-files. But it's not the slowest, either.
If you're going to use it, be sure to check in your entire project layout into the repository. This will allow you to check out an entire branch as an Eclipse project with a single click. It's very convenient, and it also allows you to version project configuration, like classpath, libraries, run-configuration, etc.
I was never involved with setting up the actual repository, but I hear it can be quite involved. With apache servers, samba, etc.
One major disadvantage: merging sucks !
But since you're the only developer in the project, you might not run into the problem too often. Also, if you're like me and you often need to compare two versions to figure out what exactly you did, you'll need an external difference viewer like Araxis, because the internal diff is just as lousy as the merge.