Owner Comments:
The 1908 is a moderately common later-date Dinero, available in mint state without too much searching. Finding a nice Gem may take some patience.
Flatt lists an 8/8, F/J, and FG/JF (with or without period below "O" in DINO; without period with 8/8). Krause adds an FG/GF, FG/JF, and 1908/6 FG/JF. The FG/GF may not be genuine, although it is conceivable the mint worker placed the letters backwards and then corrected it. All coins I have seen have no dot except my example, so the "with dot" may be considered very scarce to rare. Krause prices all 1908 varieties at the same price point, which is the correct thing to do.
NGC has one in AU 58 (1908/6 FG/JF), three in 62 at NGC (one FG/JF), one at PCGS, two in 63 at NGC, one at PCGS (FG/JF), four in 64 at NGC, one at PCGS, four in 65 at NGC (one FG/JF), one in 66 at PCGS. 17 total in mint state, 5 in Gem or better.
The set specimen is fully argent on both sides, with minimal contact. Dot below "O" in DINO. FG/JF. Lone finest for FG/JF designation. Otherwise tied with three for second place, one finer in 66.