The air is surely best done slowly, especially since it gives some opportunities for embellishments not unlike those practised by Gaelic Sean nOs singers. The only set of it I've ever seen in print (I learnt it by ear, from a Donegal Forestry worker, many years ago) is in Colm O'Lochlainn's "Irish Street Ballads", and it's a very chaste setting. According to a recent BBC TV documentary on Irish Traditional Music, it achieved wide popularity when a recording was made in the 1960s (perhaps by John Kerr?).