very important thing to remember when running amp/cab simulation:
it must be amplified using flat frequency response amplification (hi-fi, PA system, monitors, or the clean channel of modeling amps). otherwise, of you amplify a cab sim with another guitar amp, the sound shaping will double-up, and the tone will sound very nasal.
and like what was said above, consider using a small modeling amp like a Roland Cube or Blackstar ID Core as a cab sim too. A few realize that a small modeling amp + its line out is effectively neat a cab sim, which also doubles-up as a great practice rig.