As all squad based turn based games you have to relate this to the granddaddy of them all Xcom. (Or Laser Squad if you want to go a bit earlier, or Laser Squad Nemesis if you want to talk today) In the pure combat portion of this game it stands up well to the classics, unfortunetly overall if falls far short of the great one.
First off the story line here is THIN thin thin. Which if you know anything about the 40K universe is just fine since they have so much meaty story there. For those NOT familiar with the universe you'll really find nothing here to make you understand why you're fighting or what not.
Another downside to the way the game is set-up is that there is no character progression. You have nameless faceless grunts at all times. To add to this problem is that in the single player game you can't choose which units to bring, only what secondary weapons they're carrying.
In the end though the game does a good job of doing squad based tactical combat. Everything from overwatch to increased time to aim and destructible terrain is there. While the AI isn't the smartest in the world, it does a good job for the short (only 15 missions!) single player campaign. I've seen the enemy come out, shoot, and duck back to cover more times than I like. Luckily you can always blow up the cover with lots of fun weapons from Warhammer 40K.
Final Verdict: It's a 7 overall because it is a good start for what I hope would become a series of Squad based games. If they'd add the ability to choose your squad, make character growth, and the like you'd have a real contender. Add a less linear storyline and you've got a major player in the turn based strategy market.
I am not a fan of strategic combat games but I thought I should give it a try. The online component and tactics sounded intriguing. The problem was I didn't make it to the online play because the campaign was so boring I had no desire to play anyone online. the graphics are sub par and unit control is limited to point and click options only. Granted I gave up after the first level so there could be some gems in later campaign levels. I would suggest do not rent or buy this game unless you want a portal strategic conquest time of game. Poorly executed.