I usually use amp distortion. but chose the "distortion" poll because I really like the Big Muff Pi. I come up with some killer riffs with the Peavey XXX and the Muff. They work well together. MT-2 is okay, but sounds.... digital to me (lack of a better word).
all-in-all amp distortion has always been my choice.
Oh, and I also really love the Digitech Bad Monkey. Just like the one on the Gear-Monkey give-away
http://gear-monkey.com/forum/feature...al-t470.0.html
Cheers