Thanks Pete! So far I've only given this a quick, partial read, but I've already learned the answers to a few questions I've had about plating. I'm looking forward to giving this the attention it deserves.
Quote: Most likely RPM-001 imo. Mintmark position seems correct and the upright isn't visible in later die states (see WRPM-001 too: http://www.doubleddie.com/2612237.html )
Quote: Not too sure that it is a RPM-001 - I don't see the part on the bottom of the D on VV reference sire you posted. I also do not add the vertical of the D inside the Main D.
I agree with Dearborn for the reasons he listed. It could be an RPM, but I don't think it's the 001.
I'm leaning towards counterfeit. To me, it Lincoln's nose appears slightly pointed. It caught my attention right away, and while slight, it's very bothersome to me. I've compared it to several 1955 coins, both the DD and normal strikes, it still looks odd to me.
This is a nice coin! That said, I see a bit of wear on the Portrait, and some rim damage at 9 0'clock on the Reverse. It may indeed be a Proof, but it's an Impaired example.