The critics who accused Snyder as a fascist apologist and sympathizer are reaching quite a bit in my opinion.
The suffering described in the chapters dedicated to the Ukrainian famine or Stalin's purge of Katyn pale in comparison the atrocities Dirlewanger and the Waffen SS committed in their rampage across Belarus. Snyder deftly details all of these events, but there was never a doubt in my mind while reading that Hitler's regime committed worse sins than Stalin's.
As a layperson, this book came across as very thorough and fair. The amount of primary sources Snyder has pored through and synthesized is outstanding, and it's a testament to his skill as a writer that the meticulous nature of the book never really feels dull or repetitive.
If there's any singular criticism I can give, it's that Synder's thesis seems a bit self-evident: There was no worse person to be than a neutral civilian living on the eastern front in the year 1942. Not exactly a shocking revelation, but if you're interested in the history of WWII outside of a military context, this book is essential IMO.