Best Margarita/Sour Mix?

What is the best Margarita/sour mix you have found? I had an awesome margarita earlier today at a local Spanish place and the server told us the margarita mix was the lime flavor by the company “Crystal”. Long story short I can’t find any sign of it’s existence. The lady either sent me on a wild goose chase, or the language barrier between us had us completely misunderstanding each other while smiling and nodding. Have you found a mix that is your go to for a high quality margarita? If you make your own I would also love details on that!