So I'm planning to buy this pedal, but i just need a little bit more information to make up my mind:

What's the wah like? I mean, can you get like nice reggae sounds out of it, or on the other hand, like a Slash solo sound?

Whats the pitch shifter thingy like? Is it any good for stuff like the Killing in the Name of solo?
If you get the expression pedal, the wah is quite versatile I think. You can mix in distortions, so you could get both wah sounds you are talking about.

And if its like the old Zoom, then no the pitch shifter is actually just like an octaver, so is no good for Morello style whammy solos
ive got the first model of the g2.1u, and im not really big on crazy effects or anything, its got great distortion and clean sounds, with some fun effects, if your hardcore into the wah (kirk hammett style) buy wah, something like a crybaby. and i will forewarn you, i, and have heard of many others, that with the older model, the patch selection buttons as well as the rythm button have pretty muched crapped out around the 2 year mark. other than taht its a great pedal.