[Marcello]

The problem (at least this is what I remember, I haven't played much lately beyond testing) is that game ERA seems to be triggered less frequently than what would happen in the real world.But when it works it stops pretty much anything, instead of merely degrading the incoming round.
Another problem is the protection scheme.In the real world the armor protection of any tank will be different from zone to zone.
The upper glacis of an Abrams has a different composition from the lower half which in turn will offer a different amount of protection depending on the level of fuel inside the tanks.
Neverthless on western MBTs and T-55/T-62 there is a certain degree of uniformity.On T-72/T-64/T-80 the philosophy seems to offer maximum protection only in the areas most likely to be hit, at expense of the others like the lower glacis plate. And that are not the only weak spots.Think to the lack of ERA bricks behind the searchlight on T-80U.And these two are only examples.