I'm a fond fan of the Stronghold saga. I even got an appointment with a friend to get his laptop to my house, and try at the same time the LAST levels of Stronghold crusader extreme in a week or so.
The first game was really good one, the first always deserves some praise.
Then we got Crusader, almost no new things, same graphics, same buildings, just the arabic mercenaries and some little things here and there, but the endless campaign was more combat-focused, more arcade-like with not so much history, just levels and levels and a hard difficulty. Also good multiplayer values.
All of this was expanded with Crusader warchest and Crusader extreme. Both really worth the time.
Then Stronghold 2 got out, which had really improved graphics, and a lot more detail to the "castle simulation" side of things. I find this game more enjoyable on the non-combat side of the game, there so much deep into it... combat has some points too, but when there's so much things you have to care in your castle, you can't focus on combat so much.
Stronghold Legends is a good twist to the series, being in a more fantasy-oriented setting, it is original and still has the old stronghold feel to it.
Can't wait to try Stronghold 3, even i've seen some people criticising it, I'm sure I'll find something good in there.
This device requires watergineers, m'lord!