The problem I have with selecting a German tank over something like the T-34 is best described in the term "fit for purpose", there is no argument over the quality of German engineering nor the quality of its tank crews however the vehicles themselves struggled to suit the conditions they operated in.
On the Western Front where you had a very developed landscape (Quality roads, bridges etc.) German armour ruled the battlefield but on the Eastern Front those same vehicles broke down, had to be left running so they wouldn't freeze up etc. therefore I believe that the best tank of WW2 was the vehicle that could operate in all climates and conditions at maximum efficiency and to me that was the T-34.