The covenant plasma mortar tank, A.K.A. the Wraith is strong and comes with a boost feature.
Weapons:
Huge bolt of plasma that can demolish smaller vehicles and infantry
Attached plasma cannon that can kill any infantry that attempt to jack
Boost feature which propels the wraith forward and can splatter infantry
Then there is the UNSC heavy metal tank, A.K.A. the Scorpion, which has a very powerful cannon.
Weapons:
Giant cannon which can destroy aircraft, infantry, and vehicles in a matter of moments
Attached machine gun which can blast away at nearby infantry and smaller vehicles
Now comparison.
Wraith v. Scorpion
Wraith comes with boost / Scorpion doesn't
Scorpion has more controlled cannon shots than Wraith
Plasma cannon drains away at any infantry / MG is better for destroying ghosts and smaller infantry
And before you choose the scorpion, here is some information written by Fal' Taralumee that may convince you otherwise: (THIS IS NOT MY INFORMATION!!! IT WAS WRITTEN BY Fal' Taralumee so don't give me credit for it!)
I say the Wraith is better, and no, this isn't because I am a Sangheili fan. The logic is simple really. Whilst a Scorpion beats the Wraith head on, what if the Wraith was around a rock. The Wraith can shoot of the rock with its plasma mortar, hitting the Scorpion before it even gets there.
A Scorpion's shell doesn't bend or curve over, it goes straight. In comparison, the Wraith's mortar curves and dips down, hitting accuracy; distance and height. The Wraith can remain hidden and in cover whilst shooting, whereas a Scorpion can't, it will hit a wall.
Wraith's are also easier to kill hijackers where Scorpions are literally impossible unless you are near a wall. Also, the Scorpion cannot boost to quickly evade damage or hijackers which makes in vulnerable to more jacks and susceptible to more damage. However, the Wraith can use its boost to evade this.
These reasons for me, are why the Wraith is better than the Scorpion.
So now the vote
What do you guys think?