I'm not sure you'll hear a huge difference, Dood. Seymour Duncan used to make a valve guitar amp called the Convertible which had a damping factor control knob. It worked and you could hear the difference, but it never caught on. For bass, I like an amp to have tight control over the speaker myself. If I need a bit more warmth I can always get it using the tone controls.
However, Matrix obviously believe it's a good idea for guitar, and they seem to know what they are doing.