It works only as well as propagation will allow...by no means is it always 'FM Quality' sound.
One of the biggest problems with DRM is that the sidebands tend to wipe out anything that happens to be underneath them pretty effectively. It's not so different from IBOC on the MW band in that regard - DXers absolutely hate hearing about a DRM frequency near something they're trying to hear. The language, sometimes, is not to be repeated for the faint of heart (hi)
We also have links in our wiki for several sites that have information on modifying radios. However, here in the US, it will probably always be just a curiosity item - as Nick says, it's much more prevalent in Europe (where the average person is much more aware of HF broadcasting than the same person here in North America...)