Have you ever been to the Czech Rep, Slovakia, Hungary or Poland - how would you compare them to each other?

I've been to all of them, really like eastern Europe. A few weeks in Czech Rep (Brno and near Prague), a few months in Slovakia (all over the place, about 10 times over the years), a few months in Poland (Sosnowiec) and only daytrips to Hungary (Budapest and Gyor) Which country would be your favourite? I feel a certain attachment to Slovakia as it's the place I've visited the most. Never really experienced much of Hungary. Was working in Poland so it's not rreally the same as a holiday. Czech Rep is nice too. So, which is your favourite? Did you notice any major differences between the people and the countries? Thanks.