Those would be plenty good for margaritas, and you can get away with cheaper really. Do you have a Costco or Sam's Club near you? I like Kirkland's margarita mix a lot and just get that now - $11 for 1.75L, tequila already mixed in, tastes good. If you already have mix or are making them from scratch you could pick up a big 1.75L bottle of something like Hornitos reposado for under $35.