I liked Passion and Warfare for about a week. Something just seems real plastic about him. It's like he is exploiting some mathematical formula that makes him a genius guitar player by default. A formula that more often than not, completely lacks in groove. I see a huge difference between his playing and other speedsters, like Eddie Van Halen and Malmsteen. The latter two hit you where you live. Steve Vai just eggs the neighbor's house by accident and runs away.
I never even gave Satriani a chance. You always see them together in guitar mags, practically joined at the hip. If they feed off each other as influences, then no thanks. I'll wait for the next bus.