I think I hear the difference.
Can the Nebula impulse(is that what i call it) be made using the free version?
I think a proper comparison test clip is definitely in order.
we need
a: a DI track with dynamic playing going on! Heavy mutes, light mutes, volume knob usage!!!, chords, single note rhythm and slow lead lines, etc. not just chugga chugga guys!
b: that track needs to be reamped and miced through the cabinet
c: the cab sim created with the same amp/mic settings, used with the DI track reamped