ageis defence lines with defending orks! "rite lads, wes goin' ta stand behin' dis wall, and whens dey get close... Waaaggghhhh!"
serriously, you get a 4+ cover save from them, 2+ if you go to ground, 1+ if you have that special rule that is +1 to your cover save. add in some dreads, a SAG and lootas, and orks will be unmoveable.
add in the quad autocannons that can go into "overwatch" and shoot at the end of your opponents move phase and the lascannon that can shoot down Deep Strikers (i think anyway) who needs to be the attacker?
mind you, you do get to drop space ships on the enemy if you are the attacker. and the laserburn is very nice. and stormboys DS into the heart of the enemys force without old zaggy...
humm, true. This is yet again proof the Orks are smarter the Elves.