The other thread on the Razorback's upgrade got me to look at a strict comparison of the Razorback and the Wartrukk. Here goes:
Base Razorback cost: 240/40
Base Wartrukk cost: 200/30
Razorback w/RP cost: 255/55
Wartrukk w/RP cost: 250/55
So a base Razorback is a little more expensive. After the upgrade they cost the same.
Here's how they differ in terms of combat capability:
Base Razorback: 450 HP + Speed 8
Base Wartrukk: 400 HP + Speed 9
Razorback w/RP: 700 HP + Speed 10
Wartrukk w/RP: 700 HP + Speed 9
The Wartrukk also accelerates quite a bit more quickly (8 vs. 3.43), but decelerates more slowly (4 vs. 6.29).
The Wartrukk has a keen sense radius (detects infiltrated units) at a range of 30. The Razorback has the generic range of 5 for that. They both have normal sight radius of 40.
The Razorback has a DPS of 45. The Wartrukk has a DPS of 23. Their DPS degradation profiles vs. cmndr/hvyinf/vehicle are the same.
So, in essence, the upgraded Razorback gets twice the DPS and is slightly faster in exchange for the upgraded Wartrukk getting a keen sense radius of 30. (Also, the Wartrukk cannot crush cover. The Razorback can, correct?)
Before the upgrade, it's a little more complicated, but the comparison is similar.