Hey Mark, much as I love the Line6 DL4, the Line6 distortion/fuzz/overdrive emulator was horribly dissapointing!
I thought they would have much more versatitlity in the sample devices and, more importantly, really strong effects.
I think Line 6 plays way to conservatively at times. The modulation emulator, the filter emulator and the distortion emulator
all just didn't had have enough diversity and really strong effects for my particular tastes.
I'll probably get flamed for saying it.
got to love that company, if only for the Bass pod and the DL 4 though (which I am still in love with).
It's not very versatile, but for pure obnoxious FUZZ, I rather like the Boss FUZZ pedal. You don't see them around
(probably for their aforementioned lack of versatility).
There's a tribe at tribe.net called STOMPBOX PEDALS that is currently discussing fuzz boxes and recommendations.
Come check it out.