No, Unfinished Business is not the best, or even one of the best episodes of BSG, ever.
The boxing goes on for ever, and feels like a waste of time. The flashbacks are pretty decent, until the shouting declarations of love in an open field, and characters doing arbitrary things for arbitrary reasons.
I place this more as one of my least favourite episodes.
And going from a 45 minute cut and making it more expanded to ONE HOUR AND TEN MINUTES does not make it better. Good gods.
In fairness, I'm not a sports fan, so I may be missing something.