Pointed out by ACS on the Twisting the Hellmouth forums. Someone has gone to a lot of trouble on this - it's the Barbie / Oppenheimer fusion you never knew you wanted...
According to Gary Larsen's cartoon they give you a harp in Heaven and an accordion in Hell.
Assuming no knowledge of playing either instrument, and a VERY large number of people playing one in each venue, which is going to sound worse?
Update - unanimous agreement that the accordions would sound much worse because even a poorly played harp can sound OK as background noise. Thanks to all that commented.