I think it's worth upgrading to the latest QR as it's a really good system
But unfortunately, the ball bearing on the front lines can only do so much as far as keeping your lines untwisted, specially when under load.
Actually, I don't know of any kite bar system that keeps lines untwisted at any time. The closest device would be a rotating spreader bar, like the Peter Lynn ones, but even then, sometimes you have to manually rotate the thing.
Saying so, I wouldn't worry too much about that. In no time you'll learn to do backloops the other way, or front loops the same way, or just downlooping your kite during the turns, one way or the other so as to not accumulate too many twists in your lines.
And the best thing is that you'll get lots of fun doing that!