I loved and finished the first Dawn of War. I actually enjoyed the cut scenes with the storyline. The slightly camp Chaos sorcerer 'I command the darker powers" was my favourite. The kind of awesome 40K game I've been waiting for for years.
Finished Winter Assault with the 'good' side, final battle against the Necron was pretty cool but lost interest with the Ork campaign when I kept failing a level. Pretty good for an expansion I thought though. Imperial Guard were an interesting well developed new race.
I played 4 maps on Dark Crusade and uninstalled it. The Tau were an OK addition, not great though, and the Necron units are all very samey, bland and boring.
Worst of all the missions were just skirmishes and the AI is too crap to make that remotely enjoyable.
Also having picked up COH around the same time I just couldn't go back to DoW anymore.
Hopefully there will be a new DoW game using the newer engine. One day a decent turn based Final Liberation type game might be made again too.