for me, the Supernova pro takes care of the whole track. its the only synth I've got in my studio, and for now it is very capable of handling a whole track. (for strings, leads, basses, other crazy noises, etc.)

Don't forget the Waldorf Q, it's capable of making all kinda sounds -including warm ones- and the micro q has a killer price. But I agree the Virus has a warmer sound