To the OP, in case you choose GUE, there is another GUE instructor based in Egypt, Antonio Bresciani, who can teach up to CCR1 class. But I don't know him personally.
Why?
You ever seen a bad GUE diver?
If you knew who the great instructors were and could dive with them, any agency will work. I teach a great class, Jim Wyatt teaches a great class. Lots of instructors teach a great class, but you don’t even know which agency, so you certainly don’t know which instructor is going to teach a great class. So GUE.
but, if you go GUE, you’re locked into just two rebreathers. 1 scr and 1 CCR. And they both kinda suck. JJ is good, but I’m a FMCL snob.