Once you see it on the side of a truck or a billboard, it's over. You're paying their marketing budget.
Go to a "GOOD" liquor store and TALK TO THE SPIRITS BUYER. If you live in LA go to K & L Hollywood and ASK FOR THE SPIRITS BUYER. He knows more than anyone on the west coast about spirits. No joke.
My personal knowledge:
Siete Leguas - The Patron Family, sold the Patron label, still make the original deal under this label.
Cimarron
Fortaleza
Don Fulano
Any Tequila from NOM 1146
Any Tequila from NOM 1579
Tapatio. Trust me, the bottles are ugly but the Tequila is
. The son of the famed Camarena family. They also make Ocho and El Tesoro.
There's more.
Don't buy anything that is a label with a celebrity attached: E Cuarenta, Casamigos (though they sold, Clooney no longer owns it). They have nothing to do with the product and they charge you more. For example, Casamigos (George Clooney)
was made by the distillery that makes Avion, which costs less. They sold and found a new distillery to make it, or bought one. Basically, nearly every distillery in Mexico making Tequila is like a MGP and whiskey. You want a private label? They'll make one for you.