Zach is one hell of a player and a really good guy to boot.
I've had the pleasure of meeting him twice.
Once, back in 88' at East Coast music mall during a guitar clinic.
(Back then it was "Ozzy's new guy" or "Zach who??".
1st thing he said when he got up on stage is "So you guys are all here to learn about playing guitar? Well, ya ain't gonna learn sh!t here!" and ripped into a hellatious version of "sweet home alabama".
He sang all the stuff too (lots o' Black sabbath, some ozzy stuff & even some Clapton)
End of the clinic you did the meet & greet thing.
I had a Les Paul Gold top I wanted him to sign, he picked it out of the case, looked it over and played it a little. He refused to sign the front, "This thing is WAY to nice to deface it!"
Started BS'ing about guitars, beer & cars, ("dude check this out, they gave me 3 cases of beer & a Vette for a rental, who the hell is THAT stupid?!?") held up the line a little then left.

Next time was years later, used to be a club in Waterbury (can't remember the name, next to a bail bonds place. We opened for his band. Pretty freakin cool! Still A very "regular guy" & not opposed to hanging out for a beer after the show & shootin' the $hit.