I would have expected The Wild Bunch to top the list without seeing any of the Top 20's, it seems logical that the more violent type of westerns are more popular among spaghetti western fans, and Bloody Sam is of course identified with bloody violence.
Also predictable that Clint Eastwood would score high with his westerns, but it surprises me a little that his more thoughtful Unforgiven beats the more action-oriented efforts.
Ford and Hawks are still the kings of the classic western, and far more popular than others like Mann, Walsh or Boetticher.
High Noon is far more popular than Shane.
Surprisingly popular: The Hunting Party (but it is violent), Lawman (same story)
Surprisingly low marks: Ulzana's Raid, Red River (Hawks is defined as the director of the Rio Trio, so it seems)
Apart from the good marks for Ford and Hawks, I find it good to know that more thoughtful, less violence-oriented movies like Butch cassidy and the Sundance Kid, Monte Walsh, Jeremiah Johnson, The Gunfighter, Warlock and Ride the High Country are still watched and loved by younger generations. There's hope, for both the future and the past.