Which Slavic speakers have the heaviest accents in English?

[Mikula]

I am afraid that with exception of Russian and Polish accents, the most of the forum members are not familiar with accents of Slavic speakers.
Perhaps it will be better to show examples?
Here is a Czech (Dominik Hašek) speaking English , I think that it is good example how my and older generation speaks English:

[HectorOfTroy]

Poles and Russians. Poles often have such accents because the pronunciation in Polish is basically literal unlike English and Poles generally do not like to swallow vowels and want to be somewhat precise in their eloquence speaking slowly which turn out to be hilarious. But still Russian takes the cake.

North American english is pretty literal unless it's texas or nyc type area. It's brits that swallow vowels (and consonants especially). Only in britain is "water bottle" pronounced "wo'oh bo'oh"