Picking a top 5 is a very difficult undertaking, so I cheated and limited my selections to pre-war individual cards/cabinets (e.g., no team photos/postcards, press photos, etc.). And even then, this was a difficult task!
(1) 1873 Warren Studio CDV - Jim O'Rourke
(2) c1943 RPPC - Roy Campanella
(3) 1893-94 Perkins Studio Cabinet - Hughie Jennings
(4) 1898 Polensky Cabinet - Fred Clarke
(5) 1914 University of Michigan Photo Card - George Sisler


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http://imageevent.com/derekgranger
Working on the following:
HOF "Earliest" Collection (Ideal - Indiv): 250/346 (72.3%)
1914 T330-2 Piedmont Art Stamps......: 116/119 (97.5%)
Completed:
1911 T332 Helmar Stamps (180/180)
1923 V100 Willard's Chocolate (180/180)