I have just read 1632 and 1633 by Eric Flint. 1632 was an interesting story set in an alternative universe where a small American modern town ended up in Germany in 1632. I think the idea for this book was great, and that the story was very good. I especially like Gustavus Adolphus, and that he wasn’t killed in Lützen. (No more spoilers here…)
1633 was the next book in the series. David Weber helped Eric Flint with this book. Personally I guess that was the wrong person to pick for such a project. The main character became something of a super hero. Just like in his Harrington books. My friend Jonas, who read these books just before me had warned me about this. The book was still quite good, but not as good as 1632.
I’ll probably read some other book in the series since the setting was nice. There is also a RPG about this setting. From what I read about it, I guess that it would be better to use GURPS (or other generic rules) for this setting instead. GURPS Alternate Earths or Infinite Worlds would be helpful. Then You can use maps and ideas from the 1632 Fan Site.
Image from Wikimedia. Public Domain