Hi MaLer,
Sure, you can read Czech texts on Reader. I've read about 8 czech books on it and it's great. I like Reader a lot
There is only onle problem - you have to update the fonts. But it's quite simple and you are brave enough

. PDF documents should work fine even without update since they have fonts embedded in them. And, if you read a lot of topics in this forum, A4 sized PDFs are not suitable for reading on Reader.
See this thread:
https://www.mobileread.com/forums/showthread.php?t=8610