Nice example! I got mine in a job lot to flip, and just plain couldn't do it. I love the sense of speed conveyed by the galloping horse and rider on these. Mine has the bird, but on the obverse!
Nice one! Just my opinion, but I think these c. 67 B.C. later issues have a somewhat finer style to them - the 90 B.C. Social War issue was so hurried that some of the artistry leaked out.
The later issue, by C. Calpurnius Piso, is finer style overall, with high relief obverses, and it was much more carefully produced. The reverse dies for the later issue were generally convex, producing the characteristic cupping of the reverse on these coins. This helped push metal into the high relief obverse dies. The results are quite impressive in hand.
Yes, mine shows the convexity you mention. I’m not sure if you can see it better here but it’s not a flat coin but cupped.