Interestingly...the Christie suspension used on the T34 was developed by an american. The American military didn't buy the design so he sold it to the russians..
Most experts agree that the Panther was the best overall tank of WWII. Tigers were very prone to breakdowns, but they were still hard to kill and those 88mm guns were extremely deadly.
The T34 was the first tank to effectively use sloped cast armor..hence doubling or tripling the effect. It caught the Germans with their Lederhosen down and they scrambled to produce the 'panther'....it would have been simple to just reproduce the T34 except Hitler thought it would have a negative effect if the 'master race' where to stoop to copying a 'subhuman' design. also the krauts could not cast the proper quality turret.