There is a big drawback with the OKW tech though... If you destroy that building then they are screwed and have to pay to tech AGAIN - and wait for the truck.
With the USF do you need to pay for the major again if he is killed to get a tank... No.
I know you can destroy base buildings and need to pay again, but because OKW tech and building is the same thing - it's a big more complicated.
Unless you are going for the KT at which point the buildings are completely expendable.