Interestingly, I think this analysis might show the sets format gives the weaker player a better chance (depending on assumptions).
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I modified my Fargo match odds calculator to display the likely number of racks played in a match:
For a race to 9, Fargo difference of 50, the odds of the stronger player winning are 76.52 percent, and the average match length is 14.23 racks.
Compare to a Predator best-of-3-sets match, the odds of the stronger player winning are 76.12 percent, and the average match length is 13.93 racks.
So there's basically no difference in it. The formats might as well be the same from the perspective of either player.