FYI: I attend a SoBap church, and we view the baptism question this way.
Any baptism that is outside the correct method - Trinitarian, by immersion, with full knowledge that it is symbolic and not for salvation (salvation being already gained), not infant - will mostly be judged as invalid.
So to them (us) it's not being re-baptised but simply being baptised.
Just don't ask me what happens when a person who was baptised SoBap, converts at, say, age 21 to EOC, and then comes *back* to SoBap 7 years later. Don't know about that one (of course, we all know that would *never* happen
I am also thankful for the SBC's stand against liberalism - it's the most powerful American Christian group left standing against it.