My stereotypical Russian player profile is that they are very aggressive and loose players. They go very easily all-in and many of them are just gamblers. Maybe because of this aggressiveness people may think Russians are good players, aggressive style is definitely good, but no if you are just
gambling like most Russians I have met at the poker table.
And I have to disagree that it doesn't matter which country people are from. It matters a lot, I use a lot of psychological
tells, so I can recognize that. The national personality of players really affects in a poker table, Russian are straightforward and confident people, you can sense that in a poker table, also they seem very impatient at the poker table, so that's their biggest leak, aggressiveness is totally good in right situations.
This is just my own opinion and you can disagree if you want