Short answer:
One isn’t better than the other. It’s what works for you. Performance depends on mix brand, equipment, the brands and types of ingredients you add to the mix, and the skill and experience of your baker.
I’m assuming you hired a baker and obtained the formula binders from the previous owners. I’m assuming you tried the products from the bakery before you purchased it. If you liked what you sampled, then ask the previous owners what brands they used.
But do your own tests. Ask your supplier/brand rep for samples of the the mixes you are considering as well as the mixes the pervious owners used. Then have your baker make up the various products. Do blind taste tests with friends and family. Select mixes based on the product quality produced in your kitchen, by your baker, using your formula.
Long answer:
Every brand sources flour from a different mill and blend their mixes using different combinations of emulsifiers.
Flour performance is determined by wheat cultivar, protein content. ash content, starch content, extraction rate, and treatment.
Cultivar is the type of wheat: soft, hard, red, white, winter, spring.
Protein is the gliadin, glutenins, gluten
Starch is the polysaccharides or sugars
Ash is the minerals content from the soil the plant grew in
Extraction rate is the amount of the bran, endosperm, and germ left in the flour after milling.
Treatment is heat, bleaching, malted
For cupcakes and cake, you want a low protein, low ash flour. You want your protein content between 7% and 8%. You want your ash around .45 - .53. Ask the product rep for the protein and ash content of the flour they use in their mixes.
Red hard winter wheat has higher protein and higher ash. But emulsifiers can mitigate against the undesirable effects of slightly higher protein. Ask the product rep the cultivar of wheat and the type of emulsifiers used in their mixes.
Extraction rate should be about 45% for flours used in cake and cupcakes.
Bleaching and heat treatment change the molecular structure of the flour. So they rise high and produce a a much softer crumb. Some flours may be bleached only. Others may be both bleached and heated treated.
Malted means the flour is blended with barley. The barley aids browning, flavor, and texture.
There’s a mill called Central Milling that does extraordinary flours. They supply flours to the top bakeries in the country. Although they don’t make mixes I mention them only because they have a pastry flour with a whopping protein content of 10% and an ash of 1.50%. And it’s an unbleached soft wheat flour. It’s extraction rate is 100%. While it’s not llikey such a flour would be in a commercial cake mix, it demonstrates the vast range in specifications of flours used for pastry applications. You can’t assume a cake mix contains a flour with a low protein, low ash, etc. Its very important to get the specs on the flour used in a mix.