Stronghold Series on sale at Steam... but worth getting?

[JasonPratt]

I've noticed that Steam has had its Stronghold properties for sale over the past week.

I never played #1; I thought #2 was kind of poorly thought out (and buggy--so I never got far in it) but that it had potential. I've heard the best things about Stronghold Crusader (2.3333?) and the worst things about the fantasy standalone (2.6666?), but nothing at all about Stronghold 3.

Any opinions on which if any of these titles is worth picking up while on sale (or even otherwise)? Is Crusader still the height of the series, and does that mean it's worth investing time (and a little money) in?

[Nefaro]

I played the original - wasn't my thing at the time.  I recall that it was basically an RTS where you built up a castle and the AI came to attack it?  Needed something more to it, I suppose.

Dunno how it's changed over the various versions, as I've not really checked. 

[JasonPratt]

I remember Stronghold 2 involved a lot of detail in building up the castle and its surrounding society, with factions in other areas of the mission stage coming by to attack. (Although there were two campaign tracks, one of which had practically no combat.)

So, significantly more than the first game (which from what I've heard sounds like it played similar to Interplay's classic "Castles"), but also in my experience rather dodgy and not altogether well-thought-out in execution.