IMO CoH is way closer to the original Dawn of War than the DoW2 in terms of spirit. (In terms of tech, DoW 2 and CoH are much closer.)
Where CoH really shines to me is on the defensive. You can erect defensive works as your primary in game activity. Very few RTS's let you choke up the landscape with stuff, but in CoH, narrowing potential attack routes to funnel opposition in your guns is PARAMOUNT. The AI will crawl over teh battlefield and hit you from every available side when they can. That's where sandbags, razorwire, tank traps, landmines, AT guns and pill boxes come into play. You don't HAVE to play that way, but if you're not playing defensively in CoH you'd better be rushing your ass off.
As a complete tactical simulation, CoH really does it for me.
Not super historically accurate from what I've seen. It isn't that ridiculous, fairly immersive until your engineers fail to do anything at point blank range with their SMGs...
This is probably the one weak point in the game, where the battlefield simulation breaks down at close ranges. When guys are standing a decent ways apart though, it all looks pretty real.
As was said in the Company of Heroes 2 thread, CoH isn't as hardcore as Men of War, so it's not the absolute "simulationist's simulation." On the other hand, there's so many counters and things you must react to or control in CoH that it isn't your casual gamer's RTS either. Especially in competitive multiplayer, you really have to strategize against your opponents because there are many ways to attack or undermine them.
@Sirus: There are control points on the map that are split among the different kinds of resources. Holding the control points adds to your resource pools. So you don't have "harvesters" you have points of control you've got to defend or take from the enemy. These control points define "territory" on the map, and you can generally only build stuff in territory you control.
Click the Sumpf Valley link in my sig if you want to see what it looks like.
Dawn of War 2 is actually built on the same engine as Company of Heroes, so it's very very similar.
Only kind of. CoH was the Essence Engine 2. Dawn of War 2 is the Essence Engine 2.5 (and they severely dialed back the physics, level detail and terrain destruction of the engine in doing so.)