Tinkering with rubs is fun. However commercial rub companies have put in countless hours and tweaks into their product to appeal to the masses and I don't think there is anything wrong with using a commercial rub.
Rubs such as Plowboys and Simply Marvelous are amazing and quite hard to beat with a homemade rub. And both are tried and tested in peoples backyards/businesses and competitions. I don't think there is anything wrong with doing this.
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