Pitch correction on the Mic Mechanic is done fairly well - there's a wet/dry knob for it so you can choose whether you want the correction to be subtle (and it can be) or go the full Cher.
The compression works for people with poor mic technique like me. Because I'm more focused on not screwing up the bassline I adopt the lazy solution of almost always singing with my lips touching the mic. That keeps me on-axis but leaves my signal vulnerable to overload when I get excited, just ask @Silvia Bluejay. It also thickens up my voice a little, though not as effectively as my Mic Mechanic Duplicator., which is basically the same pedal but with ADT built in.