You be a sniper. Then pick any combination of 2 of the other 3 snipers. Preferably Legion since he has the upgraded sniper rifle, so drop Thane or Garrus. At this point you can just afk because their weapons have no ammo and snipers kill anything very fast.
Any other combination is just so inferior it's dumb. In fact the game's already mediocre gameplay is reduced even further due to this combination.
Tag(thx fkusumot) - "Yet again I completely fail to see your point..."
HD vs Wii, PC vs HD: http://www.vgchartz.com/forum/thread.php?id=93374
Why Regenerating Health is a crap game mechanic: http://gamrconnect.vgchartz.com/post.php?id=3986420
gamrReview's broken review scores: http://gamrconnect.vgchartz.com/post.php?id=4170835