MXR are making different distortion, all of them are great, but the most of them are specialized. This one is only distortion (no overdrive, no fuzz etc) and it is customizable for different types of music, from classic rock to heavy metal (ok, no death, trash, sludge etc, buy Boss Metal Core for it or MXR Fullbore Metal). Try to play some ZZ Top song, it sound teriffic, but if you want to play anything else it fits perfectly. It sounds dirty, so I'm not sure if you want to perform good rocking boys.
Pros:
Customizable
Strong and loud (if you want)
Strong box
Nice design
Color your tone as you want
Cons:
Not for extreme metal and pretty pop-rock
Tested on:
Gibson Les Paul
Fender Stratocaster
Marshal DSL40CR
Marshal MG10