In Texas off the shelf is Head Country original.
Their Sugar Free version is the best Sugar Free version BBQ sauce I've ever had, hands down, no competition. I've tried tons of sugar free including G. Hughes. Kinder's sugar free original comes in 2nd for sugar free. To me Kinder's sugar free is far far ahead of G. Hughes, but not good enough to beat Head Country sugar free.
Nation wide and highly available, I just go with Kraft Original BBQ sauce. Not that it really wows me but it is a good fairly straight forward bbq sauce and is consistent, no weird flavors, and widely available. I don't like how other brands/options try to move so far away from a straight forward bbq sauce. Like what is Bullseye thinking with any of their flavor profiles!?!?!?
Locally available at select places (their stores) is Rudy's BBQ Sause. Hands down the best BBQ sauce I have ever had.... period!
You can order it online but won't find it near you unless you are in Texas and have a Rudy's near you.
I buy the big liter sized bottles and give them out as gifts when I have no idea what what to get someone for a birthday, Christmas, house warming, etc. lol :)