One unanswered question that is critical to your answer is what you are using to get the sound into the PC. What sound card are you using? To have reasonable gain in Guitar Rig or other amp simulation (Amplitude, Revalver, etc.) you'll need an interface or method with the right impedance for guitar pickup input. Most of the external USB interfaces these days have at least one channel capable for this, if you want to bypass using the Mesa Boogie V-Twin.