Imho, you shouldn't be storing images and sounds on your SCM... that's not really what it's for. We store most of those externally, in a non-version-controlled environment. That really greatly reduces the space requirements (like, by a factor of 20). It also makes it much quicker to clone the repo on a new machine.

That is hard to stomach. If you're writing, for example, a game and said game has custom interface graphics, you certainly want to version those graphics along with you code. If you don't, it will be difficult to roll back to a working (and visually correct) past build.

If git is slow when I use it manage lots of binary content, that sounds to me like a problem with git rather than a problem with my workflow.

And, FWIW, git isn't too bad for managing all my data since I've broken my work into many repositories.

Oh, git isn't slow when storing binary data on it.. it's slower to clone (because you have to download all that data again), but not to use.

However, unless you are building a game or something like that, storing binaries on git will really bloat your repo so it's worth avoiding it if reasonable.

If it's assets that you do need to revert to, fair enough. But there are many "compiled" binaries that don't really need to be in the VCS, imho... and if you can err on the side of including too few binaries, you'll save a lot of space.