Looks to me to be authentic. Some of what is visible on the coin could be due to worn dies, not a perfect strike. Secondly, I am not sure that many folks would go to the trouble to produce a fake of this example.
Stylistically, it looks fine to me. I assume that there is no seam along the edge of the coin. If there is . . . Ding! Ding! Ding! Ah-ROOOO-gah!
I suppose if you're looking for something to be concerned about, one might expect more wear on the reverse given the fact that Max's hair has been all but rubbed away. But from the photo alone, I can't really ding it. Here's mine. He looks pretty cheery for a guy about to take a dive off the Milvian Bridge.
I think it is authentic. Wear can't explain the obverse, but a very worn obverse die can. At 3:30 on the OP coin there is the beginning of a die break (where metal connects the A and the G). I think the die was so worn that it broke soon after producing that coin. Freshness of die is not on everyone's radar. Wear on the coin sometimes looks like the effect of wear on the die. But, to have great detail on the coin it needs to be on the die, so the die needs to be fresh. An unworn coin from a fresh, well-engraved die can be special. Maxentius 306-312 Glossy charcoal gray. RIC Rome 210, page 378 struck "308-310"
I don’t know, but it’d likely be much easier to tell in hand. Are the letters bleeding together (A and V) and into the edge on the right hand side of the obverse of concern? I’ve read about that being a sign of casting in earlier bronzes, but I’m not sure about these later issues. The style looks normal.
