What "Iz" an "Iz"?
To be simple and short, no. It is not because the only real definition of IZ is a graffiti artist named IZ, or perhaps nicknames IZ, so no it is not allowed. And the spell check on this answer box doesn't recognize IZ.
The Wozard of Iz was created in 1968.
i iz thinkin it iz plastik
The Hawaiian musician Brudda Iz (Israel "IZ" Kaʻanoʻi Kamakawiwoʻole) is no longer with us, he died on June 26, 1997.
$&@! yes it iz. it iz th best genre out ther
Cali Iz Active was created in 2005.
Iz U was created on 2003-12-09.
a pulse iz cauzed cuz i said it iz caused
Fantje iz gline was created in 2005.
pe pe pe vagina
There is no "PE" as in commands, but there is Windows PE.