I actually have both. In the 431 a blued 3" and the 720 is the fixed sight DAO fluted cyl model.
Both guns have good lockup with the Rossi being slightly more tight, but the taurus actually has stronger bolt engagement and the better sights between the two. The Rossi also has the best DA trigger, in fact it's right in there with a good K frame S&W. It has the better trigger profile vs the wide serrated trigger on the Taurus- but the taurus might be favorable for SA shooting.
Both shoot pretty well, my hunch is the Taurus is more accurate and has better chamber throat dimensions vs the Rossi, which I believe are slightly oversized.
At any realistic range, the Rossi is plenty accurate, but I can't hold the kind of groups I can with the taurus shooting DA or SA. The Rossi favors lead cowboy type ammo whereas the Taurus is less particular and will shoot cowboy stuff about as well as Gold Dots...and it's done well in the snubby match with gold dots.
Both guns chrono 800-850fps with the Blazer Gold Dot 200gr, but the Taurus is consistently 30-40fps faster, even though they have same bbl lengths. Nothing crazy there, it's normal and variation like that isn't unheard of between two identical model bbl lengths, etc.
For a carry gun, I'd lean slight toward the Rossi since it's slightly thinner and has the better DA trigger (at least on my DAO gun), the Taurus might be the better all rounder or range shooter.