I could tell you a little about Germany since I live there. Sweden and Finland I have never been to but had many friends tell me its awesome.
Czech republic I have been to with my grandfather some 8-9 years ago because he wanted to visit relatives before he was going to die. I cannot remember much of the country, only that the people had been very friendly. A lot might have changed since then.
So if you should need some more info about Germany, feel free to pm me.