Possibly the best squad-based RTS I've played...
Defensive positioning is pretty good and at times, you have to hand-hold the squads from being simply crushed by the enemy's charges. Either way, it's the only RTS that I'm currently playing and I haven't gotten bored with it at all as both the single player and the multiplayer entertain for quite a while.
I put the learning curve to 30-60 minutes because that's about how long I took the really get the game's mechanics but it might take some longer and others shorter. All in all, I say it's best in its series.