[vintagetoppsguy]

I would go with '56 Topps for the following reasons:

• There are no "big" rookies (unlike say the '54 or '55 Topps sets), so that keeps it more affordable.
• You also have some nice second and third year cards of players like Aaron, Koufax, Killebrew, Kaline, Banks and Clemente.
  
• Nice mantle card (maybe the best looking card in the set) after taking a 2 year break from Topps.
  
• Many, many other HOFers from the set such as Mays, T. Williams, J. Robinson, Kaline, Mathews, Spahn, Snider, Berra - probably at least 30 HOFers in the set (just guessing).
  
• Not as many cards to complete the set as in later Topps years.
  
• First year for team cards and checklists.

I could go on and on, but it's certainly my favorite set from that decade.