In the end, I ended up trying Shark Warzy Drive with a Schecter Blackjack ATX C-1 (which was randomly given to me.)
It had been at G77 since long time ago but I never had a chance to try it.
1. I was too lazy to try.
2. There's always someone else trying something else.
First impression on it: it is just like any other metal distortion, or so I thought. Its distortion would be somewhat special, especially if you are the type who play Visual Kei. It has the 'Japanese' feeling (as I would term it) which couldn't really be explained in words. However, anyone exposed to such Japanese music will immediately recognise it. I guess this is why this pedal is so popular in Japan.
It has double boost feature, which I think is rather excessive. One boost would have been more than sufficient. Double-boost is just too noisy.