Topband: 300 ohm twin lead for bidirectional Beverage antennas

[Joe Giacobello, K2XX]

I'm considering putting up two bidirectional Beverage RX antennas.  It 
appears that most of the recommendations for Beverages consider the 
close spacing of 300 ohm twin lead undesirable for reasons that are not 
entirely clear, but the consensus if far from unanimous.  I'd like to 
hear the judgment of this list's Beverage experts on the question?

Thanks for your input.

73, Joe
K2XX