Redstone Flux is in it's infancy as a power source. True, at the moment, 5 dynamos and some hardened conduit will run every single one of your machines at maximum power, though only one at a time. But even that is wholly unnecessary. TE also introduces energy cells, which can store RF power, and more importantly be picked up and maintain that power. So if my base is full of power, and a friend needs some power to start his base back up, I can pick up my power cell and go to his base and plug in my cell. No need to haul stacks of coal coke to fire up his boilers, no need to worry, is my battery the right tier to plug into his power system or do I need to bring the correct connection piece and appropriate transformers so I don't turn it into a crater. I just plug and play.
More than that, it has an exact equivalency to MJ. RF is precisely a 10:1 ratio, so I know exactly how many MJ I'm making, or how many RF I need to produce to run something. Redstone Flux compatibility is nice to have, but it's not essential, which is great, because it goes out of it's way to make itself MJ compatible, even though there's NO reason for it to bother, other than legacy reasons. They could have just made it it's own power system, completely separate from MJ, and no one would have complained. (Okay, that's a lie. Someone always complains.) Instead, they decided to leave the compatibility, so that it could unify the mods. It won't work completely, because nothing should, but having RF as a common standard of transformation between systems could be useful. As in RF is 10:1 MJ, and X:X EU could be useful as mod makers try to balance systems.