Not sure how anybody can say Mirallas is a better player considering how little time he's actually had on the pitch. Career movement (Drenthe being bought by Real while Mirallas never really impressed in France and ended up playing in Greece) suggests Royston has more ability.
Let's not fall into the trap of over hyping Kev when he's barely played, Drenthe is a hell of a player when he wants to be.
The ability, hunger and work-rate shown by belg Kev compares favourably with the likes of Eden hazard, Angel Di Maria, Alexis Sanchez and in a lesser sense Theo Walcott. Drenthe just looked like a talented but deeply flawed player who will frustrate more than not.