Are you referring to the original DAB (using MP2) or the upgraded DAB+ standard (using HE-AACv2)? I think most, if not all, stations have switched to DAB+. I'm told the quality is better than FM and based on my experience it's certainly not worse as far as I can hear. Of course, since FM is analog it degrades linearly whereas DAB+ is digital: it either works or it doesn't. This might skew the perception of quality.