From all the details I've come across, these two are supposed to be used at the same time. The comparison I've seen describes BPC as the supervisor directing the crew while TB500 functions like the vehicles that speed supplies to the damaged spot.
From what I've seen, folks seem to feel that using both together works better than relying on just one by itself. How did things go in your own trials? It caught me off guard how much pricier this option turned out to be compared with the other. I'm wondering if spending more actually pays off.