Oh and in Zamoysky's defence he did write a monograph about the border battles, Battle for the Marchlands which was generally well reviewed. Alas it's out of print and nigh impossible to find.
Warsaw 1920
is Battle for the Marchlands basically reissued. Presumably his fame has made his earlier monograph now marketable. It is disappointing that he didn't take new information into account.
I prefer the Battle of the Marchlands to White Eagle Red Star on balance, but they are pretty similar. Both are better than Warsaw 1920 to a wargamer.