For a software bounce there's obviously no difference.
But just to confuse things... there is probably another way you could bounce, that some folks do use.
You could, if you wanted to, decide that you prefer the sound of the summing bus of your interface (rather than Pro-Tools) and bounce using this. I'm not too familiar with the Focusrite boxes, but Metric Halo users do this all the time - bouncing via a digital loopback thus ensuring that the MH box is doing the summing and not your DAW.
I assume something like this would be technically possible with the Focusrite, although whether it would be subjectively better or worse than an internal Pro-Tools bounce I can't honestly say. All I can say is that in my experience the summing bus of my Metric Halo is smoother and appears to leave more space around the mix than summing in Logic, so I always use this method on mission-critical mixes.
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