I also use vinegar based (again, with reduced sugar).
I’m not overly fond of mayo (even “good” mayo), so we usually don’t do that one.
Interesting about the pork butt. I was thinking maybe allulose would work well, since it will brown. However, what we usually do (don’t tell anyone) is just use regular brown sugar. When it’s all said and done, and I’m smoking 5+ pounds of meat, there’s not a lot of sugar on what I actually eat. And so much falls off.
I also use a sous vide recipe (sous vide with rub for a long time), and then cool, dry, put more rub on, then smoke a short time. There’s really no way to know how much rub is on there.
I also think if you’re one of those people who count calories/carbs, this is one of those instances where you have to give up. It’s impossible to know how much you’re getting.