I've had a brief struggle with trying to get the standalone executables to work under Linux, without any success (I'm told that they probably are incompatible with my server's kernel version; note that the documentation does not state what kernel or OS versions are supported). Similarly, I've had a brief look at what it'd take to set up an install using BOSH.. but it looks like that's going to be a massive undertaking.
As a practical matter, if you want to use Concourse for real work, you probably do have to jump in with BOSH right away, since the standalone versions are likely not to work with your VMs, and the vagrant version is missing critical features and hasn't even been updated to the 1.0 release.