The flan has looks like similar to a couple of my Caracalla sestertii, good size but narrow in width - a very pleasing look. Both of these are spectacular coins.
One more comment on the issue of flans - I once had a Dive Faustina sestertius that had a flan that was identical in all respects to a Commmodus sestertius I had - you put the two coins (carefully) on top of each other and the flans, which were a bit uneven, matched in all respects - absolutely the same. What does it indicate? Perhaps that Diva Faustina sestertii were being struck in the reign of Commodus - perhaps why they seem to be a bit common side - or that the flan molds were used for years and years. Or none of the above - maybe the mold was set aside by mistake and rediscovered during the reign of Commodus - absent a mint masters diary from this period, which I doubt will ever be found if it ever existed, it is tough to speculate about these things. What would such a diary say, in Latin of course?: "dated 888 years from the founding of Roma. While looking for a slave who was suspected of sleeping behind some old barrels, found a dusty sestertii mold, that had been used for coins of the divine empress Faustina back in the the reign of the divine Antoninus Pius. Has odd shape almost like a half lyre, gave it to Plautinus to be used for sestertii of our beloved emperor. " I know really bad but time is short it is the best I could do. The math was a guess and is no doubt way off.