I believe that all tier 10 heavy ones that have a low height can easily beat the E-100 if they approach and touch the side of the E-100. What I'm saying is in a 1vs1 battle, where the player can easily approach the enemy.
I would say the biggest advantage the IS7 has over the E100 is that your turret can't get spammed with gold shells. Seriously! I might as well call my E100 "Fort Knox" with how much gold gets thrown at it in the average battle.
That's why I prefer to use an IS7 because it's a lower profile which the high profile tanks like the E100 and Maus can't pen it if they get closer and the armor itself is a slope curvy so sometimes shells can always bounce and it's hard to pen it
Well even though I make videos like that, we can't really say which tank is better for everything, cause every tank has it's advantages and dissadvantages.
Suggestion: European Line Vs Germany. Currently, both the European line and the German line have 7 tier 10s. My suggestion is to make a team with all tier 10s side by side, in this case the European team will have 1 more midfielder while the German team will have a fighter tank too much. I hope the text was easy to understand, I did it using Google Translate.