owned both; would personally recommend the rotor given its ease of use and quick strip down time.
having said that, the prophecy is notciably lighter than the rotor and has a far larger mouth so less (if any) ball spillage. Despite what people have been saying about the feedneck snapping, i never had that problem but then again, I did fork out £13 or so to get myself an aluminium feedneck shipped over from the States.
The Prophecy has a plethora of customizable settings and its ridiculously overpriced LTD upgrade board pretty much covers all the bases. Very easy on paint and reballs. The speedfeed is also pretty decent unlike its DYE counterpart.
However, I opted to go the Rotor route cos:-
a). insane battery life
b). ease of operation "single on/off button"
c). strips down in 20secs or less
d). everything else i had was pretty much DYE branded^^
if you get a 2nd hand rotor, try and make sure it is one of the later genereations with the velcro battery straps and sharkfin anti-jam paddle. The sharkfin update is a significant update IMO and really helps to unjam your jam.
In summary,
Prophecy vs 1st gen rotor (velcro battery straps update)....get a Prophecy
Prophecy vs 2st gen rotor (velcro straps + fin upgrade)....get the rotor