Is this an improvement on what's already in the saltstack/develop branch? By checking both lxc-autostart (only in new versions) and lxc-version (not in 1.0), you get some version checking without shelling out. But I'm not 100% certain when lxc-autostart was added, so maybe the tests should be in the other order (lxc-version, display deprecation warning, otherwise check for lxc-somethingelse and return True)