....
So yes, the Opel blitz is better because it provides more resources in a doctrine that actually HAS ways to effectively make use of the increased resource generation, unlike soviets.
Not is not Opel and Zis-6 truck are identical so they are the same.
You might want to argue that the it is available is a better commander is better but even that is questionable.
Assault support commander is not that popular in any mode being in load around middle for top players while lend lease is popular in 1vs1 scoring being around 6.
I doubt thou that anyone picks those commanders for the truck and I am pretty sure that if truck are used the spend more time on fuel than MU.
In sort a clear case of the grass is greener on the other side of the fence, the unit are simply identical.