Radiant heating in basements should not be used to dry out a basement. They can actually pull more moisture into the home by moving water through the slab faster. I've seen several people do this in damp areas of Canada...only to discover their dehumidifier is now pumping to the max and yet everything gets wetter and wetter.

To stop the damp smell, you need to look at moisture remediation. Adding in floor radiant heat to an entire basement is expensive...moisture mitigation can be few bucks cheaper (they can be the same price). So you might as well get the proper work done for the same money as radiant heated floors...and be done with "musty".