Tonebone hot brit is an intense Distorion that will crush any metal pedal out there. Its pricy but well worth it. here is the link
http://www.tonebone.com/tb-hotbritish.htm
If your wallet lacks the funds, well I fount that the Electro Harmonix pedal called "the
metal muff" unbelievable!
YOu are forking out 100 bucks for an amzing pedal.
here is the link as well.
https://www.ehx.com/ehx2/Default.asp?q=f&f=%2FCatalog%2F001%5FXO%5FLine%2F28%5FMetal%5FMuff
My other disovery is the cooltron
Bull Dog from Vox. amazing distortion but a bit pricy for what it is. I rather invest on on the Tonebone hot brit.
also, try out the new Kerry King EQ from Mxr. What a diffrence an EQ could make.
Boss distrotion are heavy but lose bottom when cranked unless you have a great amp. Tone bone sounds good on any amp.